Release v0.6.42: use compact pinned checkbox beside history search

CMakeLists.txt

@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.24)
-project(KSwitcher VERSION 0.6.28 LANGUAGES CXX RC)
+project(KSwitcher VERSION 0.6.42 LANGUAGES CXX RC)
 if(NOT WIN32)
   message(FATAL_ERROR "KSwitcher uses native Windows APIs")
 endif()
@@ -48,6 +48,7 @@ else()
 endif()
 add_executable(KSwitcherOcrTests tests/ocr.cpp src/screenshot_launcher.cpp src/screenshot_activation.cpp src/app.cpp src/screenshot_notifications.cpp src/screenshot.cpp src/configuration.cpp src/ui.cpp resources/app.rc)
 target_link_libraries(KSwitcherOcrTests PRIVATE kscore)
+add_dependencies(KSwitcherOcrTests KSwitcherScreenshot)
 if(MSVC)
   set_property(TARGET kscore KSwitcher KSwitcherConfig KSwitcherScreenshot KSwitcherTests KSwitcherScrollTests KSwitcherIntegration KSwitcherInputTests KSwitcherOcrTests PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
   target_compile_options(kscore PRIVATE /W4 /utf-8)
@@ -65,6 +66,49 @@ else()
   target_link_options(KSwitcherOcrTests PRIVATE -static -static-libgcc -static-libstdc++)
 endif()
 enable_testing()
+add_executable(KSwitcherHistoryHostTests tests/history_host.cpp)
+target_link_libraries(KSwitcherHistoryHostTests PRIVATE kscore psapi)
+set_target_properties(KSwitcherHistoryHostTests PROPERTIES RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/history-host-fixture-$<CONFIG>")
+add_dependencies(KSwitcherHistoryHostTests KSwitcher KSwitcherScreenshot)
+add_custom_command(TARGET KSwitcherHistoryHostTests POST_BUILD
+  COMMAND ${CMAKE_COMMAND} -E copy "$<TARGET_FILE:KSwitcher>" "$<TARGET_FILE_DIR:KSwitcherHistoryHostTests>/KSwitcher.exe"
+  COMMAND ${CMAKE_COMMAND} -E copy "$<TARGET_FILE:KSwitcherScreenshot>" "$<TARGET_FILE_DIR:KSwitcherHistoryHostTests>/KSwitcher.Screenshot.exe"
+  COMMAND ${CMAKE_COMMAND} -E touch "$<TARGET_FILE_DIR:KSwitcherHistoryHostTests>/.local-dev")
+if(MSVC)
+  target_compile_options(KSwitcherHistoryHostTests PRIVATE /utf-8)
+  set_property(TARGET KSwitcherHistoryHostTests PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
+else()
+  target_link_options(KSwitcherHistoryHostTests PRIVATE -static -static-libgcc -static-libstdc++)
+endif()
+add_executable(KSwitcherClipboardSnapshotTests tests/clipboard_snapshot.cpp)
+target_link_libraries(KSwitcherClipboardSnapshotTests PRIVATE kscore psapi)
+add_dependencies(KSwitcherClipboardSnapshotTests KSwitcherScreenshot)
+if(MSVC)
+  target_compile_options(KSwitcherClipboardSnapshotTests PRIVATE /utf-8)
+  set_property(TARGET KSwitcherClipboardSnapshotTests PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
+else()
+  target_link_options(KSwitcherClipboardSnapshotTests PRIVATE -static -static-libgcc -static-libstdc++)
+endif()
+add_executable(KSwitcherImageCaptureTests tests/image_capture.cpp)
+target_link_libraries(KSwitcherImageCaptureTests PRIVATE kscore)
+add_dependencies(KSwitcherImageCaptureTests KSwitcherScreenshot)
+if(MSVC)
+  target_compile_options(KSwitcherImageCaptureTests PRIVATE /utf-8)
+  set_property(TARGET KSwitcherImageCaptureTests PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
+else()
+  target_link_options(KSwitcherImageCaptureTests PRIVATE -static -static-libgcc -static-libstdc++)
+endif()
+# Explicit interactive test: stop the resident first so its clipboard listener
+# does not capture the test fixtures. Like KSwitcherIntegration, not part of ctest.
+add_executable(KSwitcherDictionaryTests tests/dictionary.cpp)
+target_link_libraries(KSwitcherDictionaryTests PRIVATE kscore psapi)
+if(MSVC)
+  set_property(TARGET KSwitcherDictionaryTests PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
+else()
+  target_link_options(KSwitcherDictionaryTests PRIVATE -static -static-libgcc -static-libstdc++)
+endif()
+add_test(NAME dictionary-regressions COMMAND KSwitcherDictionaryTests)
+set_tests_properties(dictionary-regressions PROPERTIES WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}")
 add_test(NAME sync-regressions COMMAND KSwitcherSyncTests)
 add_test(NAME native-regressions COMMAND KSwitcherTests)
 add_test(NAME scroll-regressions COMMAND KSwitcherScrollTests)

README.md

@@ -16,10 +16,15 @@ Run `build/KSwitcher.exe`, or extract `dist/KSwitcher-win-x64.zip` and run the e
 The build also refreshes the release copy in `build/release/`. Exit KSwitcher before rebuilding.
 The application lives in the notification area. Right-click its icon for Settings, Snippets and history.
 Double-click the tray icon to open Settings, the bold default menu item.
+Closing Settings with unsaved changes (including accepted auto-correction or OCR options)
+asks whether to save, discard changes, or keep editing. Unchanged settings close without a prompt.
+If saving fails, the window stays open with your edits intact.
 Menus support access keys: press the underlined letter while the menu is open (for example,
 S for Settings or X for Exit in the tray menu). In forms, press Alt+the underlined letter
-to activate a button, toggle a checkbox or focus a labeled field. Press Alt to reveal
-the underlines when Windows hides them. Shortcut-capture fields still record Alt combinations;
+to activate a button, toggle a checkbox or focus a labeled field. Dialog underline visibility
+still follows Windows preferences; press Alt in a dialog to reveal them.
+From v0.6.33, tray and history menus show access letters in the right-hand column.
+Press the menu letter without Alt: Alt dismisses an open menu. Shortcut-capture fields still record Alt combinations;
 press Tab to leave a shortcut field before using form access keys.
 Settings, the snippet editor and log viewer run on demand in **KSwitcher.Config.exe**, beside the main executable.
 Repeated launches activate the existing configurator; closing its last window exits that process.
@@ -170,7 +175,8 @@ for shapes.
 **Canvas zoom:** use **Ctrl++ / Ctrl+-** (including numpad keys) or **Ctrl+mouse wheel**.
 Each step changes the view by 25%; the wheel zooms around the cursor, keyboard shortcuts around
 the viewport center. **Ctrl+0** restores the initial fit. Drag with the **middle mouse button**
-to pan an enlarged image. Zoom ranges from 0.1× to 16× the initial fit; the status bar shows the
+to pan an enlarged image. Panning is limited to axes where the image exceeds the viewport;
+an image that fits stays centered. Zoom ranges from 0.1× to 16× the initial fit; the status bar shows the
 actual image scale. Zoom and pan do not change annotations, export resolution or undo history.
 The wheel without Ctrl still adjusts the object under the cursor.
 
@@ -186,6 +192,9 @@ Every shape has a round rotation handle above its outline. Drag it to rotate aro
 hold **Shift** for 15-degree steps. The handle works for toolbar shapes and recognized shapes,
 including triangles. Resize handles and attached connectors follow the rotation; Ctrl+Z/Ctrl+Y
 undo and redo it. The square handle still controls outline thickness.
+From v0.6.34, endpoint, shape-corner and number-radius handles show the four-direction move cursor.
+Thickness handles retain directional resize cursors; rotation retains the hand cursor. Dragging,
+snapping and shape constraints are unchanged.
 **Triangle (G)** is also available directly on the toolbar: drag to create a triangle.
 Both drawn and recognized triangles have three independent vertex handles instead of bounding-box
 resize handles. Drag any vertex to reshape the triangle while keeping the other two fixed, even
@@ -271,7 +280,11 @@ thumbnails and source labels aligned with the scaled fonts and spacing.
 - Clipboard snapshot/restoration with concurrent-copy, foreground and input-version checks.
   A silently dropped copy is retried up to three total attempts while the clipboard and input
   context remain unchanged. Temporary transaction contents are excluded from Windows clipboard
-  history and cloud synchronization. Paste is not blindly retried.
+  history and cloud synchronization. Paste is not blindly retried: with manual paste readback
+  enabled by Write log, a native Windows EDIT gets at most one retry when readback reports the
+  original and fresh native queries confirm that exactly the original range is still selected.
+  Other controls and unknown/changed selections are not retried. A verified failed paste clears
+  repeat-conversion state and does not switch the Windows layout.
 - Case cycling, Russian/Ukrainian transliteration, verified undo and repeated conversion.
 - Text snippets across layouts, multiline insertion and a verified `{cursor}` position;
   `{enter}` presses Enter after insertion and cursor placement (once per marker), before buffered typing resumes.
@@ -321,6 +334,10 @@ existing saved shortcuts are preserved. While KSwitcher runs, this binding opens
 
 History controls: Enter to paste, Shift+Enter for plain text, Ctrl+1…9 for quick paste,
 Ctrl+P to pin/unpin, Delete to delete, Ctrl+O for the full item, Escape to hide.
+
+**Clear history… / Alt+H** in the history window clears all saved entries after confirmation,
+including pinned entries and entries hidden by search. No is the default choice. The current
+Windows clipboard and future recording are unchanged. Settings also retains its Clear history action.
 For an image, **Edit image**, **Ctrl+O**, or **Edit image in screenshot editor**
 in the context menu opens the original image in the built-in screenshot editor.
 Annotate it there, then copy the result. Opening the editor leaves the
@@ -610,7 +627,12 @@ support automatic correction. Dictionary recognition is heuristic, not an unders
 subtitle vocabulary is incomplete, and uncommon names or jargon can need personal exceptions.
 
 No network service or language model is used. The three dictionary files occupy about 2.6 MB on disk;
-the English/Ukrainian lookup data uses less than 3 MiB of RAM and is loaded on first automatic check.
+the bundled EN/UK/RU lookup payload uses about 0.90 MiB of RAM. When automatic correction is enabled,
+selected dictionaries are loaded before typing and shared by the input predictor and worker.
+Words are stored in compact indexed blocks; all words and frequency ranks are retained, and editable
+UTF-8 dictionary files keep the same format. Custom dictionaries can use more memory.
+`build.ps1 -Test` checks every bundled word/rank and measures lookup speed; CMake exposes the same
+check as `dictionary-regressions`. The payload figure excludes the rest of the process and allocator overhead.
 Keep `dictionaries/` beside the executable when copying the app. These word lists derive from
 [FrequencyWords](https://github.com/hermitdave/FrequencyWords) and are separately licensed under
 CC BY-SA 4.0; attribution, pinned source revision and license are in `dictionaries/`.
@@ -681,3 +703,31 @@ Keep `v0.4.2` as the last legacy `vX.Y.Z` release. Publish full packages as
 legacy version tag: clients that have not installed the bridge would select it.
 Keep the compatibility bridge in the first 100 releases returned by Gitea while
 supporting old clients; their immutable update code only reads that page.
+
+### Editors that omit copied trailing spaces
+
+From v0.6.31, KSwitcher recovers trailing ordinary spaces omitted by Ctrl+C only when Windows accessibility proves the complete selection. The same focused control and range are rechecked before paste, and the result is read back even without Write log. Recent-text conversion, automatic correction, repeat conversion and Undo retain exact verification. Missing letters, tabs, line breaks and unavailable or ambiguous selections are not reconstructed. No setting or shortcut has changed.
+
+### Notification registration and Viber — v0.6.36
+
+Notification registration runs in KSwitcher.Screenshot.exe; keep all three executables together. Startup registration is asynchronous. Viber pastes allow 75 ms for clipboard notifications before Ctrl+V, retaining focus, ownership and selection checks. This mitigates an intermittent clipboard timing issue; it does not guarantee all Viber failures are resolved. UI Automation is unchanged.
+
+### Image history, OCR and duplicate fingerprints — v0.6.37
+
+Image clipboard capture and automatic/uncached manual history OCR run in short-lived KSwitcher.Screenshot.exe processes. Keep all three executables together. Original clipboard formats, image limits, privacy exclusions, Windows OCR, optional Tesseract and searchable encrypted OCR results are preserved. Background OCR is cancelled on shutdown or an OCR-profile change; late results do not recreate deleted entries.
+
+Consecutive duplicates use SHA-256 fingerprints inside the encrypted history index, including pixel fingerprints for equivalent image encodings. Older entries acquire fingerprints on first comparison without a bulk migration. Pins and OCR caches survive duplicate detection; non-consecutive copies still create separate entries. New text no longer loads the preceding image to rule out a duplicate. No shortcut, setting or default changed.
+
+Moving OCR isolates its temporary memory rather than reducing the combined processing peak. A controlled three-run comparison retained about 0.8 MiB less private RAM in the caller after recognition; combined peak RAM was about 55.6 MiB before and 56.6 MiB with the helper. Results depend on the image, OCR engine and system.
+
+### Pinned history checkbox — v0.6.42
+
+Check **★ Pinned only** beside the history search box to show only pinned entries; uncheck it to show all entries. The checkbox sits on the left, immediately followed by the search box; its right edge stays aligned with the history list when resizing. The text search applies within that filter. Unpinning an item removes it from the pinned view immediately. The checkbox state and search are remembered after closing and reopening history. **Clear history…** still deletes the entire history after confirmation, including entries hidden by the filter.
+
+### History process and clipboard memory — v0.6.40
+
+History opens in a separate, short-lived instance of **KSwitcher.exe**. **Esc** closes it even when focus is on the window or an action button, releasing Windows UI allocations with the process. The resident keeps keyboard hooks, clipboard capture and history storage. Search, selection and the top entry are preserved in encrypted view state. If a full-text item viewer is still open, the helper stays alive until the last viewer closes. Pin/delete, formatted/plain paste and OCR remain available; settings and default shortcuts are unchanged.
+
+Image thumbnails are decoded in **KSwitcher.Screenshot.exe**, returning only bounded preview pixels. Image clipboard backup/restore also uses that helper and encrypted temporary files, with clipboard-sequence checks before restoring. Selection reads avoid loading image formats. Keep all three executables together; no fourth executable is required. Paste allows a brief foreground handoff after history closes while preserving cancellation checks. UI Automation remains in the resident.
+
+A live development-build test measured **4.37 MiB before history and 4.35 MiB after two open/Esc cycles**, compared with an earlier roughly 8–9 MiB plateau. A same-image clipboard-backup benchmark retained **12.78 MiB before versus 0.05 MiB after**. These measure private working set, not a guaranteed total footprint. Include all helpers when measuring active use: combined memory can be higher while history is open. No forced working-set trimming is used. Existing screenshots and shortcuts remain applicable. The v0.6.38 approach of retaining a hidden history window/RichEdit control is superseded by process termination.

Release/README.md

@@ -1,30 +1,21 @@
 # Latest Windows release
 
-## v0.6.28 — 2026-11-02
+## v0.6.42 — 2026-11-04
 
 ## Changes
-- Custom automatic replacement pairs and optional dictionary typo correction. Both are off by default; enable Automatic correction and the desired modes in Auto-correction options. Custom pairs take priority; dictionary correction accepts one unambiguous single edit in words of at least four letters. Case, punctuation, exclusions and Undo are preserved.
-- First synchronization now merges independent entries immediately. Different values for one setting remain pending as individual conflicts instead of requiring Download/Upload of a whole profile.
-- Optional partial sync keeps this PC's layout cycle and direct shortcuts while syncing other settings. Existing server layouts and bindings are preserved, including during explicit Upload. Missing-layout errors identify the language where available and exact layout IDs.
-- Disabled synchronization disables dependent controls. Save can persist disabling without connecting; forgetting the saved password remains available. Status messages can be selected, copied and scrolled.
-- Selection diagnostics record expected/copied text before and after recovery, clipboard sequences and retries, timing, focus/caret information and context interruptions. Failed verification now includes expected and actual text. Context retains up to 128 events for 30 seconds.
+- Replaced the history filter dropdown with a one-click **★ Pinned only** checkbox. Checked shows pinned entries; unchecked shows all entries.
+- The checkbox sits on the left, with the search field immediately alongside it. The search field keeps its right edge aligned with the history list when the window is resized.
+- Existing filter state, search, Unpin behavior and persistence across Esc are preserved. No shortcut or default changed. Clear history still deletes every entry after confirmation, including hidden entries.
 
 ## Validation
-105 sync/protocol/conflict checks and 483 native regression checks and 48 updater checks passed. All 12 manifest files and all three executable versions were verified in the release ZIP. Focused partial-sync UI checks and screenshot PNG-save regressions passed. During development, conversion/diagnostic and typo integration scenarios passed, including Undo and uninterrupted typing. Final interactive input testing is limited by this execution session reporting no foreground window; the full screenshot UI suite also failed its pan assertion at 240 DPI. These interactive checks are not claimed as passing.
+The dedicated 500-entry history integration suite verifies checkbox clicks, combined search/filter, removal after Unpin, remembered state after helper restart, text/image paste and helper shutdown. The compact layout was checked visually in the installed development build.
 
-## Limitations
-Dictionary typo correction is experimental and has no sentence context. Ambiguous words are unchanged. The reported asynchronous selection mismatch in ChatGPT is not fixed by the new diagnostics; full-range verification still cancels unsafe replacements. OpenBao synchronization remains experimental and requires HTTPS, KV v2 and a provisioned userpass account/policy. Ordered layout/language lists are resolved as whole settings; partial mode keeps the entire local layout configuration. Update participating PCs together for the new profile fields. No account registration, MFA, non-root namespaces or reverse-proxy URL prefixes.
+The release build also passed dictionary equivalence (140,939 words), 105 sync checks, 315 native checks, 561 input checks, screenshot UI/save/registration, 48 updater checks and updater progress UI.
 
-**Upgrade:** choose Update in the tray menu. Legacy v0.3.0–v0.4.1 clients first receive the v0.4.2 compatibility bridge, then the current full release. v0.2.3 and earlier require manual installation.
+## Upgrade
+Choose **Update** in the tray menu. Legacy v0.3.0–v0.4.1 clients first receive the v0.4.2 compatibility bridge, then the current full release. v0.2.3 and earlier require manual installation.
 For manual installation, exit KSwitcher, close screenshot editors and extract the entire ZIP into its installation folder. Keep personal `data/` and customized dictionaries.
 
-Download **KSwitcher-win-x64.zip** with **SHA256SUMS.txt**. The package includes all three executables, a release manifest, offline dictionaries, documentation and license notices. No personal settings, passwords, server address or clipboard history are included.
+Download **KSwitcher-win-x64.zip** with **SHA256SUMS.txt**. Keep all three executables together; history uses another instance of KSwitcher.exe, so no fourth executable is required. The package contains no personal settings, credentials or clipboard history.
 
-Build and package:
-
-```powershell
-.\build.ps1 -Stage -Test
-.\package.ps1 -PublishRelease
-```
-
-Publish stable `release-vX.Y.Z` tags matching the executable version. Keep `v0.4.2` as the last legacy tag.
+Publish stable `release-vX.Y.Z` tags matching the executable version. Keep `v0.4.2` as the last legacy tag.

Release/SHA256SUMS.txt

@@ -1 +1 @@
-c15937f52c981e7c6b15203aae51ae47dd2a261b495bd458533b01fd4cfe5498  KSwitcher-win-x64.zip
+67cb67d4c08a8722fdd91bb513a9254d781cbee524d2e2eb39721251503b01c9  KSwitcher-win-x64.zip

build.ps1

@@ -37,10 +37,14 @@ try {
     if ($LASTEXITCODE) { throw 'Configurator link failed' }
     Copy-Item -LiteralPath $configPath -Destination build/release/KSwitcher.Config.exe -Force
     $screenshotPath = Join-Path (Split-Path $executablePath) 'KSwitcher.Screenshot.exe'
-    & $compiler -mwindows -municode -static -s '-Wl,--gc-sections' build/core.o build/platform.o build/ocr.o build/screenshot.o build/screenshot_notifications.o build/screenshot_activation.o build/screenshot_main.o build/screenshot-res.o @libs -o $screenshotPath
+    & $compiler -mwindows -municode -static -s '-Wl,--gc-sections' build/core.o build/platform.o build/storage.o build/ocr.o build/screenshot.o build/screenshot_notifications.o build/screenshot_activation.o build/screenshot_main.o build/screenshot-res.o @libs -o $screenshotPath
     if ($LASTEXITCODE) { throw 'Screenshot link failed' }
     Copy-Item -LiteralPath $screenshotPath -Destination build/release/KSwitcher.Screenshot.exe -Force
     if ($Test) {
+        & $compiler @common tests/dictionary.cpp build/core.o build/platform.o build/autocorrect.o @libs -lpsapi -static -s -o build/KSwitcherDictionaryTests.exe
+        if ($LASTEXITCODE) { throw 'Dictionary test build failed' }
+        & .\build\KSwitcherDictionaryTests.exe
+        if ($LASTEXITCODE) { throw 'Dictionary tests failed' }
         & $compiler @common tests/sync.cpp build/core.o build/platform.o build/storage.o build/sync.o build/ocr.o @libs -static -s -o build/KSwitcherSyncTests.exe
         if ($LASTEXITCODE) { throw 'Sync test build failed' }
         & .\build\KSwitcherSyncTests.exe
@@ -77,15 +81,35 @@ try {
         if ($LASTEXITCODE) { throw 'Updater progress UI tests failed' }
     }
     if ($Integration) {
+        $historyFixture = Join-Path (Resolve-Path build) ('history-host-fixture-' + [guid]::NewGuid().ToString('N'))
+        New-Item -ItemType Directory $historyFixture | Out-Null
+        Copy-Item $executablePath,(Join-Path (Split-Path $executablePath) 'KSwitcher.Screenshot.exe') -Destination $historyFixture
+        Set-Content (Join-Path $historyFixture '.local-dev') 'Isolated history integration test'
+        $historyTest = Join-Path $historyFixture 'KSwitcherHistoryHostTests.exe'
+        & $compiler @common tests/history_host.cpp build/core.o build/platform.o build/storage.o build/ocr.o @libs -lpsapi -static -s -o $historyTest
+        if ($LASTEXITCODE) { throw 'History host test build failed' }
+        & $historyTest
+        if ($LASTEXITCODE) { throw 'History host tests failed' }
+        $snapshotTest = Join-Path (Split-Path $executablePath) 'KSwitcherClipboardSnapshotTests.exe'
+        & $compiler @common tests/clipboard_snapshot.cpp build/core.o build/platform.o build/storage.o build/ocr.o @libs -lpsapi -static -s -o $snapshotTest
+        if ($LASTEXITCODE) { throw 'Clipboard snapshot test build failed' }
+        & $snapshotTest
+        if ($LASTEXITCODE) { throw 'Clipboard snapshot tests failed' }
+        $captureTest = Join-Path (Split-Path $executablePath) 'KSwitcherImageCaptureTests.exe'
+        & $compiler @common tests/image_capture.cpp build/core.o build/platform.o build/storage.o build/ocr.o @libs -static -s -o $captureTest
+        if ($LASTEXITCODE) { throw 'Image capture test build failed' }
+        & $captureTest
+        if ($LASTEXITCODE) { throw 'Image capture tests failed' }
         & $compiler @common tests/integration.cpp build/core.o build/platform.o build/autostart.o build/autocorrect.o build/storage.o build/sync.o build/ocr.o build/richtext.o build/update.o build/screenshot.o build/screenshot_launcher.o build/screenshot_activation.o build/screenshot_notifications.o build/app.o build/configuration.o build/ui.o build/screenshot-res.o @libs -static -s -o build/KSwitcherIntegration.exe
         if ($LASTEXITCODE) { throw 'Integration test build failed' }
         & .\build\KSwitcherIntegration.exe
         if ($LASTEXITCODE) { throw 'Integration tests failed' }
     }
     if ($Ocr) {
-        & $compiler @common tests/ocr.cpp build/core.o build/platform.o build/autostart.o build/autocorrect.o build/storage.o build/sync.o build/ocr.o build/richtext.o build/update.o build/screenshot.o build/screenshot_launcher.o build/screenshot_activation.o build/screenshot_notifications.o build/app.o build/configuration.o build/ui.o build/screenshot-res.o @libs -static -s -o build/KSwitcherOcrTests.exe
+        $ocrTest = Join-Path (Split-Path $executablePath) 'KSwitcherOcrTests.exe'
+        & $compiler @common tests/ocr.cpp build/core.o build/platform.o build/autostart.o build/autocorrect.o build/storage.o build/sync.o build/ocr.o build/richtext.o build/update.o build/screenshot.o build/screenshot_launcher.o build/screenshot_activation.o build/screenshot_notifications.o build/app.o build/configuration.o build/ui.o build/screenshot-res.o @libs -static -s -o $ocrTest
         if ($LASTEXITCODE) { throw 'OCR test build failed' }
-        & .\build\KSwitcherOcrTests.exe
+        & $ocrTest
         if ($LASTEXITCODE) { throw 'OCR tests failed' }
     }
     foreach ($folder in @('build/dictionaries','build/release/dictionaries','build/staged/dictionaries')) {

resources/app.rc

@@ -9,8 +9,8 @@ IDC_SCREENSHOT_PENCIL CURSOR "icons/lucide/pencil.cur"
 1 RT_MANIFEST "app.manifest"
 201 RCDATA "update.ps1"
 1 VERSIONINFO
- FILEVERSION 0,6,28,0
- PRODUCTVERSION 0,6,28,0
+ FILEVERSION 0,6,42,0
+ PRODUCTVERSION 0,6,42,0
  FILEOS VOS_NT_WINDOWS32
  FILETYPE VFT_APP
 BEGIN
@@ -20,7 +20,7 @@ BEGIN
   BEGIN
    VALUE "FileDescription", "KSwitcher — native keyboard and clipboard utility"
    VALUE "ProductName", "KSwitcher"
-   VALUE "FileVersion", "0.6.28"
+   VALUE "FileVersion", "0.6.42"
   END
  END
  BLOCK "VarFileInfo"

src/app.cpp

@@ -1,4 +1,5 @@
 #include "app.h"
+#include <utility>
 #include "../vendor/json.hpp"
 #include "../resources/resource.h"
 #include "ocr.h"
@@ -14,6 +15,7 @@ namespace ks
 {
 #include "app_sync.inl"
 App *App::current = nullptr;
+#include "app_history.inl"
 namespace
 {
 const char *transformCommandName(int command)
@@ -70,12 +72,14 @@ class Transaction
     App &app;
     HWND target;
     uint64_t version;
-    Clip snapshot;
+    ClipboardSnapshot snapshot;
     DWORD expected{};
     bool captured{};
     mutable bool invalidLogged{};
     unsigned copyNumber{};
     std::wstring adopted;
+    std::unique_ptr<PasteProbe> selectionProof;
+    std::wstring provenSelection;
 
   public:
     Transaction(App &a, HWND t, uint64_t v) : app(a), target(t), version(v)
@@ -84,7 +88,7 @@ class Transaction
         try
         {
             expected = GetClipboardSequenceNumber();
-            snapshot = readClipboard(app.window, 64 * 1024 * 1024);
+            snapshot.capture(app.window, expected);
             if (expected != GetClipboardSequenceNumber())
                 throw std::runtime_error("Clipboard changed while taking snapshot");
             captured = true;
@@ -100,7 +104,7 @@ class Transaction
         if (captured && GetClipboardSequenceNumber() == expected)
             try
             {
-                app.ownSequence = writeClipboard(app.window, snapshot);
+                app.ownSequence = snapshot.restore(app.window, expected);
             }
             catch (...)
             {
@@ -128,7 +132,7 @@ class Transaction
         if (GetClipboardSequenceNumber() != expected)
         {
             auto now = GetClipboardSequenceNumber();
-            if (adopted.empty() || !ownsClipboard(target) || readClipboard(app.window).text() != adopted ||
+            if (adopted.empty() || !ownsClipboard(target) || readClipboard(app.window, 32 * 1024 * 1024, ClipboardRead::Selection).text() != adopted ||
                 GetClipboardSequenceNumber() != now)
                 throw std::runtime_error("Operation cancelled: another application changed the clipboard");
             expected = now;
@@ -150,7 +154,7 @@ class Transaction
         if (GetClipboardOwner() != app.window)
             throw std::runtime_error("Clipboard changed immediately after writing");
         auto text = c.text();
-        if ((!text.empty() && readClipboard(app.window).text() != text) ||
+        if ((!text.empty() && readClipboard(app.window, 32 * 1024 * 1024, ClipboardRead::Selection).text() != text) ||
             GetClipboardSequenceNumber() != expected)
             throw std::runtime_error("Clipboard changed while verifying our write");
     }
@@ -224,7 +228,7 @@ class Transaction
             changed != GetClipboardSequenceNumber())
             throw std::runtime_error("Operation cancelled: copy did not belong to the target application");
         expected = changed;
-        auto clip = readClipboard(app.window);
+        auto clip = readClipboard(app.window, 32 * 1024 * 1024, ClipboardRead::Selection);
         auto text = clip.text();
         diagnosticEvent(L"Copy result number=" + std::to_wstring(number) + L" attempts=" +
             std::to_wstring(attempts) + L" elapsedMs=" + std::to_wstring(GetTickCount64() - started) +
@@ -250,8 +254,27 @@ class Transaction
                 }
             }
         }
+        selectionProof.reset();
+        provenSelection.clear();
+        // Viber and some other editors omit trailing ASCII spaces from Ctrl+C.
+        // Recover only from a real selection, never from the recorded keys alone.
+        if (valid() && !text.empty() && text.size() < 8192 && text.back() != L' ')
+        {
+            auto proof = std::make_unique<PasteProbe>(true, target);
+            auto selected = proof->read(1, false);
+            if (selected && selected->size() > text.size() && selected->starts_with(text) &&
+                selected->find_first_not_of(L' ', text.size()) == std::wstring::npos && valid())
+            {
+                diagnosticEvent(L"Copy: trailing spaces verified via accessibility copied=" +
+                    diagnosticText(text) + L" selected=" + diagnosticText(*selected));
+                text = *selected;
+                provenSelection = text;
+                selectionProof = std::move(proof);
+            }
+        }
         return text;
     }
+    bool recoveredSelection() const { return selectionProof != nullptr; }
     bool select(size_t n)
     {
         return selectPrevious(n, [&] { return valid(); });
@@ -324,9 +347,26 @@ class Transaction
     }
     bool paste(const Clip &clip)
     {
+        if (selectionProof)
+        {
+            auto selected = selectionProof->read(1, false);
+            if (!selected || *selected != provenSelection || !valid())
+            {
+                diagnosticEvent(L"Paste cancelled: recovered selection changed or unavailable");
+                return false;
+            }
+        }
         if (!valid())
             return false;
         write(clip);
+        // Viber's Qt editor observes clipboard changes asynchronously. Give it
+        // a chance to discard the data object from Ctrl+C before requesting paste.
+        // Recheck ownership and input below; never retry a possibly applied paste.
+        if (lower(processName(target)) == L"viber")
+        {
+            Sleep(75);
+            diagnosticEvent(L"Paste: Viber clipboard notification settling interval completed");
+        }
         for (int i = 0; i < 2; ++i)
         {
             check();
@@ -338,9 +378,36 @@ class Transaction
         Sleep(300);
         return true;
     }
+    bool nativeSelectionIs(const std::wstring &original) const
+    {
+        if (!valid()) return false;
+        GUITHREADINFO gui{sizeof(gui)};
+        if (!GetGUIThreadInfo(GetWindowThreadProcessId(target, nullptr), &gui) || !gui.hwndFocus) return false;
+        wchar_t cls[32]{};
+        GetClassNameW(gui.hwndFocus, cls, 32);
+        if (_wcsicmp(cls, L"Edit") != 0 ||
+            (GetWindowLongPtrW(gui.hwndFocus, GWL_STYLE) & (ES_PASSWORD | ES_READONLY))) return false;
+        auto query = [&](UINT message, WPARAM wp, LPARAM lp, DWORD_PTR &result)
+        {
+            return SendMessageTimeoutW(gui.hwndFocus, message, wp, lp,
+                                       SMTO_ABORTIFHUNG | SMTO_BLOCK, 100, &result) != 0;
+        };
+        DWORD_PTR range{}, length{}, copied{};
+        if (!query(EM_GETSEL, 0, 0, range) || (DWORD)range == 0xffffffff ||
+            size_t(HIWORD(range) - LOWORD(range)) != original.size() ||
+            !query(WM_GETTEXTLENGTH, 0, 0, length) || length > 65534 || HIWORD(range) > length) return false;
+        std::wstring content(length + 1, L'\0');
+        if (!query(WM_GETTEXT, content.size(), (LPARAM)content.data(), copied) || copied != length) return false;
+        DWORD_PTR after{};
+        GUITHREADINFO focused{sizeof(focused)};
+        return query(EM_GETSEL, 0, 0, after) && after == range && valid() &&
+               GetGUIThreadInfo(GetWindowThreadProcessId(target, nullptr), &focused) && focused.hwndFocus == gui.hwndFocus &&
+               content.substr(LOWORD(range), original.size()) == original;
+    }
 };
 } // namespace
-App::App(HINSTANCE h, bool test, const std::filesystem::path &dataRoot) : instance(h), smoke(test)
+App::App(HINSTANCE h, bool test, const std::filesystem::path &dataRoot, HWND service)
+    : historyService(service), instance(h), smoke(test)
 {
     updateNotifier = notifyUpdateAvailable;
     current = this;
@@ -357,7 +424,7 @@ App::App(HINSTANCE h, bool test, const std::filesystem::path &dataRoot) : instan
         registrationWarning = L"Settings were not loaded: " + wide(e.what());
     }
     setLoggingEnabled(settings.writeLog);
-    if (settings.autoCorrect)
+    if (settings.autoCorrect && !historyService)
         try { autoPredictor.configure(std::filesystem::path(executable()).parent_path() / L"dictionaries", settings.autoLanguages); }
         catch (const std::exception &e)
         {
@@ -376,6 +443,9 @@ App::App(HINSTANCE h, bool test, const std::filesystem::path &dataRoot) : instan
 }
 App::~App()
 {
+    if (auto host = historyController(historyProcess)) PostMessageW(host, WM_CLOSE, 0, 0);
+    if (historyProcess) CloseHandle(historyProcess);
+    if (notificationRegistration) CloseHandle(notificationRegistration);
     if (syncWorker.joinable()) syncWorker.join();
     if (updateWorker.joinable())
         updateWorker.join();
@@ -470,7 +540,10 @@ void App::scheduleHistoryOcr(const Settings &config)
                         if (!entry.image || (entry.ocrState != 1 && entry.ocrProfile == profile)) continue;
                         try
                         {
-                            auto text = recognizeText(history->load(entry.id), config);
+                            auto text = history->recognizeImage(entry.id, config, [this, &profile] {
+                                std::lock_guard lock(jobsMutex);
+                                return stop || ocrProfile(historyOcrSettings) != profile;
+                            });
                             std::lock_guard lock(jobsMutex);
                             if (stop || ocrProfile(historyOcrSettings) != profile) continue;
                             if (history->saveOcr(entry.id, text, config))
@@ -586,7 +659,7 @@ void App::applySettings(const Settings &requested)
         ++inputVersion;
         if (busy) diagnosticEvent(L"Input context changed: settings applied version=" + std::to_wstring(inputVersion.load()));
     }
-    // Clear on the worker so the next check reloads edits to dictionary files.
+    // Release the worker's old snapshot; the next check shares the freshly loaded predictor.
     enqueue([this] { autoCorrector.configure({}, {}); });
     scheduleHistoryOcr(s);
     nextSync = std::max(GetTickCount64() + 2000, syncRetryAfter);
@@ -619,6 +692,7 @@ void App::reloadLayouts()
 }
 void App::clearHistory()
 {
+    if (historyService) { remoteHistory("clear"); history->reload(); return; }
     if (busy) throw std::runtime_error("Wait for the current operation to finish.");
     if (history) history->clear();
     if (historyWindow) refreshHistory(*this);
@@ -647,6 +721,13 @@ void App::resetInput()
     run.reset();
     last.reset();
 }
+void App::releaseIdleMemory(ULONGLONG now)
+{
+    expireDiagnostics(now);
+    std::lock_guard lock(stateMutex);
+    // Match the Undo eligibility deadline; never discard an available operation.
+    if (!busy && last && now - last->at > 120000) last.reset();
+}
 void App::clearLog(bool previous) { clearDiagnosticLog(previous); }
 void App::keyboard(const KBDLLHOOKSTRUCT &k, UINT mods)
 {
@@ -1110,9 +1191,11 @@ void App::transform(int command, int snippet)
                     if (!config.autoCorrect || recent.window != target || recent.overflow ||
                         recent.keys.empty() || recent.keys.back() != L' ' || hint < 0)
                         return;
-                    autoCorrector.configure(std::filesystem::path(executable()).parent_path() /
-                                                L"dictionaries",
-                                            config.autoLanguages);
+                    {
+                        std::lock_guard lock(stateMutex);
+                        if (inputVersion.load() != version) return;
+                        autoCorrector.shareDictionaries(autoPredictor);
+                    }
                     std::wstring predicted;
                     for (wchar_t key : recent.keys)
                         predicted += key == L' ' ? L' ' : available[hint].at(physicalLayout().code(key));
@@ -1263,6 +1346,11 @@ void App::transform(int command, int snippet)
                         actual = text;
                         verification = L"selection-mismatch";
                         reason = L"previous-result-verification-mismatch";
+                        {
+                            std::lock_guard lock(stateMutex);
+                            last.reset();
+                            run.reset();
+                        }
                         if (tx.valid())
                             chord(VK_RIGHT);
                         return;
@@ -1310,13 +1398,30 @@ void App::transform(int command, int snippet)
                     }
                 }
                 bool sent = false;
-                PasteProbe probe(config.writeLog && manual && result != text, text);
+                const bool requireReadback = tx.recoveredSelection();
+                PasteProbe probe(((config.writeLog && manual) || requireReadback) && result != text, text, target);
+                if (requireReadback && result != text && probe.status != L"ready")
+                {
+                    reason = L"recovered-selection-unavailable";
+                    std::lock_guard lock(stateMutex);
+                    last.reset();
+                    run.reset();
+                    return;
+                }
                 diagnosticEvent(L"Conversion source=" + std::to_wstring(hint) + L" target=" + std::to_wstring(to) +
                     L" changed=" + std::to_wstring(result != text));
                 if (result != text)
                     sent = tx.paste(textClip(result));
                 else if (automatic && tx.valid())
                     chord(VK_RIGHT);
+                if (requireReadback && result != text && !sent)
+                {
+                    reason = L"recovered-selection-paste-cancelled";
+                    std::lock_guard lock(stateMutex);
+                    last.reset();
+                    run.reset();
+                    return;
+                }
                 if (sent || result == text)
                     autoSelected = false;
                 reason = result == text ? L"conversion-unchanged" :
@@ -1326,19 +1431,48 @@ void App::transform(int command, int snippet)
                     reason = L"Conversion unchanged";
                     verification = L"calculated-result-equals-original";
                 }
-                if (sent && manual && config.writeLog)
+                if (sent && ((manual && config.writeLog) || requireReadback))
                 {
                     verification = probe.status;
                     if (tx.valid())
                     {
                         auto observed = probe.read((int)caretSteps(result));
+                        // A native Edit may silently ignore Ctrl+V while the clipboard is busy.
+                        // Retry once only with fresh native proof that the exact original range
+                        // is still selected. Never retry an unknown or changed editor state.
+                        if (observed && newlines(*observed) == newlines(text) && tx.nativeSelectionIs(text))
+                        {
+                            diagnosticEvent(L"Paste retry: native Edit still selects the unchanged original");
+                            if (tx.paste(textClip(result)) && tx.valid())
+                                observed = probe.read((int)caretSteps(result));
+                            else
+                                observed.reset();
+                        }
                         verification = probe.status;
                         if (observed && tx.valid())
                         {
                             actual = *observed;
                             reason = conversionReadbackOutcome(newlines(actual), newlines(text), newlines(result));
+                            if (newlines(actual) != newlines(result))
+                            {
+                                std::lock_guard lock(stateMutex);
+                                last.reset();
+                                run.reset();
+                                diagnosticEvent(L"Paste rejected by readback: previous result cleared; layout not switched");
+                                return;
+                            }
+                        }
+                        else
+                        {
+                            reason = L"Paste not verified";
+                            if (requireReadback)
+                            {
+                                std::lock_guard lock(stateMutex);
+                                last.reset();
+                                run.reset();
+                                return;
+                            }
                         }
-                        else reason = L"Paste not verified";
                     }
                     else verification = L"context-changed-after-paste";
                 }
@@ -1394,6 +1528,7 @@ void App::transform(int command, int snippet)
 }
 void App::pasteEntry(std::wstring id, bool plain)
 {
+    if (historyService) { remoteHistory("paste", id, plain); return; }
     if (installingUpdate) return;
     if (!history || busy.exchange(true))
         return;
@@ -1415,10 +1550,20 @@ void App::pasteEntry(std::wstring id, bool plain)
             } reset{busy};
             try
             {
-                for (int i = 0; i < 20 && !modifiersReleased(); ++i)
+                // Foreground activation crosses a process boundary when the
+                // history UI closes. Let the destination finish activation,
+                // while retaining the same input-version cancellation guard.
+                for (int i = 0; i < 20 && inputVersion == version &&
+                     (!modifiersReleased() || GetForegroundWindow() != target); ++i)
                     Sleep(10);
                 if (!modifiersReleased() || GetForegroundWindow() != target || inputVersion != version)
+                {
+                    log(L"History paste cancelled before transaction: foreground=" +
+                        std::to_wstring(GetForegroundWindow() == target) + L" modifiers=" +
+                        std::to_wstring(modifiersReleased()) + L" expectedVersion=" + std::to_wstring(version) +
+                        L" actualVersion=" + std::to_wstring(inputVersion.load()));
                     return;
+                }
                 auto clip = history->load(id);
                 if (plain)
                 {
@@ -1428,7 +1573,7 @@ void App::pasteEntry(std::wstring id, bool plain)
                     clip = textClip(text);
                 }
                 Transaction tx(*this, target, version);
-                tx.paste(clip);
+                log(tx.paste(clip) ? L"History paste: simulated paste completed" : L"History paste cancelled before simulated paste");
             }
             catch (const std::exception &e)
             {
@@ -1459,7 +1604,19 @@ void App::captureHistory()
                 for (auto &name : config.excluded)
                     if (lower(name) == lower(app))
                         return;
-                auto clip = readClipboard(window, (size_t)config.maxImageMiB * 1024 * 1024);
+                if (IsClipboardFormatAvailable(CF_DIB) || IsClipboardFormatAvailable(CF_DIBV5) ||
+                    IsClipboardFormatAvailable(CF_BITMAP) ||
+                    IsClipboardFormatAvailable(RegisterClipboardFormatW(L"PNG")))
+                {
+                    if (history->captureImage(sequence, app, config))
+                    {
+                        scheduleHistoryOcr(config);
+                        PostMessageW(window, HistoryMessage, 0, 0);
+                    }
+                    return;
+                }
+                auto clip = readClipboard(window, (size_t)config.maxImageMiB * 1024 * 1024,
+                                          ClipboardRead::WithoutImages, sequence);
                 if (sequence != GetClipboardSequenceNumber())
                     return;
                 for (auto &f : clip.formats)
@@ -1478,6 +1635,7 @@ void App::captureHistory()
 }
 void App::recognizeEntry(std::wstring id)
 {
+    if (historyService) { remoteHistory("ocr", id); return; }
     if (!history || busy.exchange(true))
         return;
     auto sequence = GetClipboardSequenceNumber();
@@ -1496,7 +1654,9 @@ void App::recognizeEntry(std::wstring id)
             try
             {
                 auto cached = history->ocrText(id, ocrProfile(config));
-                auto text = cached ? *cached : recognizeText(history->load(id), config);
+                auto text = cached ? *cached : history->recognizeImage(id, config, [this] {
+                    std::lock_guard lock(jobsMutex); return stop;
+                });
                 if (!cached) history->saveOcr(id, text, config);
                 if (text.empty())
                 {
@@ -1547,6 +1707,7 @@ void App::trayMenu()
     GetCursorPos(&pt);
     pasteTarget = GetForegroundWindow();
     SetForegroundWindow(window);
+    showMenuAccessKeys(menu);
     int cmd = TrackPopupMenu(menu, TPM_RETURNCMD | TPM_RIGHTBUTTON, pt.x, pt.y, 0, window, nullptr);
     DestroyMenu(menu);
     PostMessageW(window, WM_NULL, 0, 0);
@@ -1645,7 +1806,37 @@ LRESULT CALLBACK App::windowProc(HWND hwnd, UINT msg, WPARAM wp, LPARAM lp)
     auto *app = current;
     if (!app)
         return DefWindowProcW(hwnd, msg, wp, lp);
-    if (msg == app->taskbarCreated && app->taskbarCreated)
+    if (app->historyService) {
+        if (msg == HistoryHostShow || msg == HistoryHostRefresh) {
+            try {
+                app->history->reload();
+                if (msg == HistoryHostShow) showHistory(*app);
+                else if (IsWindowVisible(app->historyWindow)) refreshHistory(*app);
+            } catch (const std::exception &e) { app->report(wide(e.what())); }
+            return 0;
+        }
+        if (msg == WM_TIMER) {
+            if (!IsWindow(app->historyService)) PostMessageW(hwnd, WM_CLOSE, 0, 0);
+            return 0;
+        }
+        if (msg == WM_CLOSE) {
+            EnumThreadWindows(GetCurrentThreadId(), [](HWND child, LPARAM) -> BOOL {
+                wchar_t name[64]{}; GetClassNameW(child, name, 64);
+                if (std::wstring(name) == L"KSwitcher.Entry" || std::wstring(name) == L"KSwitcher.History")
+                    DestroyWindow(child);
+                return TRUE;
+            }, 0);
+            DestroyWindow(hwnd);
+            return 0;
+        }
+        if (msg == WM_DESTROY) { PostQuitMessage(0); return 0; }
+        if (msg == ErrorMessage) {
+            std::unique_ptr<std::wstring> text(reinterpret_cast<std::wstring *>(lp));
+            MessageBoxW(app->historyWindow, text->c_str(), L"Clipboard history", MB_OK | MB_ICONWARNING);
+            return 0;
+        }
+    }
+    if (!app->historyService && msg == app->taskbarCreated && app->taskbarCreated)
     {
         app->addTray();
         return 0;
@@ -1759,6 +1950,7 @@ LRESULT CALLBACK App::windowProc(HWND hwnd, UINT msg, WPARAM wp, LPARAM lp)
     case WM_COPYDATA:
     {
         auto *data = (COPYDATASTRUCT *)lp;
+        if (data && data->dwData == HistoryRequest) return app->historyRequest((HWND)wp, *data);
         if (data && data->dwData >= ConfigRead && data->dwData < ConfigEnd)
         {
             if (app->installingUpdate) return FALSE;
@@ -1775,6 +1967,15 @@ LRESULT CALLBACK App::windowProc(HWND hwnd, UINT msg, WPARAM wp, LPARAM lp)
     case WM_TIMER:
         if (wp == 6)
         {
+            if (app->notificationRegistration && WaitForSingleObject(app->notificationRegistration, 0) == WAIT_OBJECT_0)
+            {
+                DWORD code = ERROR_GEN_FAILURE;
+                GetExitCodeProcess(app->notificationRegistration, &code);
+                if (code) log(L"Screenshot notification registration helper failed: " + std::to_wstring(code));
+                CloseHandle(app->notificationRegistration);
+                app->notificationRegistration = nullptr;
+            }
+            app->releaseIdleMemory(GetTickCount64());
             app->pollSync();
             return 0;
         }
@@ -1836,7 +2037,7 @@ int App::execute()
     WNDCLASSW cls{};
     cls.hInstance = instance;
     cls.lpfnWndProc = windowProc;
-    cls.lpszClassName = L"KSwitcher.Main";
+    cls.lpszClassName = historyService ? HistoryHostClass : L"KSwitcher.Main";
     cls.hIcon = LoadIconW(instance, MAKEINTRESOURCEW(IDI_KSWITCHER));
     RegisterClassW(&cls);
     window = CreateWindowExW(WS_EX_TOOLWINDOW, cls.lpszClassName, L"KSwitcher", WS_POPUP, 0, 0, 0, 0, nullptr,
@@ -1870,6 +2071,30 @@ int App::execute()
             }
             CoUninitialize();
         });
+    if (historyService) {
+        try {
+            auto bytes = unprotect(readFile(data / L"history-view.bin", 4 * 1024 * 1024));
+            auto state = HistoryJson::parse(bytes);
+            historySelection = wide(state.value("selection", std::string{}));
+            historyTop = wide(state.value("top", std::string{}));
+            historyQuery = wide(state.value("query", std::string{}));
+            historyPinnedOnly = state.value("pinnedOnly", false);
+        } catch (...) {}
+        showHistory(*this);
+        remoteHistory("ready", std::to_wstring(reinterpret_cast<uintptr_t>(historyWindow)));
+        SetTimer(window, 1, 1000, nullptr);
+        MSG message{};
+        while (GetMessageW(&message, nullptr, 0, 0) > 0) {
+            if (message.message == WM_KEYDOWN && message.wParam == VK_ESCAPE && historyWindow &&
+                (message.hwnd == historyWindow || IsChild(historyWindow, message.hwnd))) {
+                SendMessageW(historyWindow, WM_CLOSE, 0, 0);
+                continue;
+            }
+            if (historyWindow && message.message == WM_SYSCHAR && IsDialogMessageW(historyWindow, &message)) continue;
+            TranslateMessage(&message); DispatchMessageW(&message);
+        }
+        return int(message.wParam);
+    }
     keyboardHook = SetWindowsHookExW(WH_KEYBOARD_LL, keyProc, instance, 0);
     mouseHook = SetWindowsHookExW(WH_MOUSE_LL, mouseProc, instance, 0);
     registerHotkeys(settings);
@@ -1893,7 +2118,7 @@ int App::execute()
         log(std::wstring(L"Update completed; running version ") + AppVersion);
     if (startCommand)
         PostMessageW(window, WM_HOTKEY, startCommand, 0);
-    try { registerScreenshotNotifications(); }
+    try { notificationRegistration = startScreenshotNotificationRegistration(); }
     catch(const std::exception &e) { log(L"Screenshot notification registration: "+wide(e.what())); }
     auto screenshotActivation=startScreenshotActivationListener();
     MSG msg;
@@ -1906,7 +2131,7 @@ int App::execute()
                 continue;
         }
         // Preserve history-specific Enter/Shift+Enter and Ctrl+digit handling.
-        if (historyWindow && msg.message == WM_SYSCHAR && IsDialogMessageW(historyWindow, &msg))
+        if (!isolateHistory && historyWindow && msg.message == WM_SYSCHAR && IsDialogMessageW(historyWindow, &msg))
             continue;
         if (settingsWindow && IsDialogMessageW(settingsWindow, &msg))
             continue;

src/app.h

@@ -33,6 +33,11 @@ class App
 {
   public:
     HWND window{}, historyWindow{}, settingsWindow{}, snippetsWindow{};
+    HWND historyService{}; // Non-null only in the short-lived history UI process.
+    bool isolateHistory{};
+    unsigned historyEntryWindows{};
+    std::wstring historySelection, historyTop, historyQuery;
+    bool historyPinnedOnly{};
     HINSTANCE instance{};
     std::filesystem::path data;
     std::vector<Layout> layouts;
@@ -55,7 +60,7 @@ class App
     bool smoke{};
     int startCommand{};
     std::wstring updateStartupEvent;
-    App(HINSTANCE, bool = false, const std::filesystem::path &dataRoot = {});
+    App(HINSTANCE, bool = false, const std::filesystem::path &dataRoot = {}, HWND historyService = nullptr);
     ~App();
     int execute();
     void dispatch(int);
@@ -72,6 +77,11 @@ class App
     void applySettings(const Settings &);
     void reloadLayouts();
     void clearHistory();
+    void openHistoryProcess();
+    void refreshHistoryProcess();
+    void remoteHistory(const char *action, const std::wstring &id = {}, bool plain = false);
+    LRESULT historyRequest(HWND, const COPYDATASTRUCT &);
+    void saveHistoryView(const std::wstring &, const std::wstring &, const std::wstring &, bool);
     void clearLog(bool previous);
     void setHotkeyCapture(HWND);
     bool isHotkey(DWORD, UINT);
@@ -86,11 +96,14 @@ class App
 
   private:
     friend struct InputRegressionAccess;
+    void releaseIdleMemory(ULONGLONG now);
     HHOOK keyboardHook{}, mouseHook{};
+    HANDLE historyProcess{};
     std::mutex jobsMutex;
     std::condition_variable jobsReady;
     std::deque<std::function<void()>> jobs;
     std::thread worker;
+    HANDLE notificationRegistration{};
     std::thread historySearchWorker;
     std::condition_variable historySearchReady;
     std::function<void()> pendingHistorySearch;

src/app_history.inl

@@ -0,0 +1,100 @@
+// History UI has no clipboard listener or hooks. The resident remains the only writer.
+namespace {
+constexpr ULONG_PTR HistoryRequest = 0x4b530200;
+constexpr UINT HistoryHostShow = WM_APP + 71, HistoryHostRefresh = WM_APP + 72;
+constexpr wchar_t HistoryHostClass[] = L"KSwitcher.HistoryHost";
+using HistoryJson = nlohmann::json;
+HWND historyController(HANDLE process)
+{
+    if (!process || WaitForSingleObject(process, 0) == WAIT_OBJECT_0) return nullptr;
+    auto window = FindWindowW(HistoryHostClass, nullptr);
+    DWORD pid{}; GetWindowThreadProcessId(window, &pid);
+    return pid == GetProcessId(process) ? window : nullptr;
+}
+}
+void App::openHistoryProcess()
+{
+    auto foreground = GetForegroundWindow();
+    if (foreground != window && foreground != historyWindow) pasteTarget = foreground;
+    if (historyProcess && WaitForSingleObject(historyProcess, 0) == WAIT_OBJECT_0) {
+        CloseHandle(historyProcess); historyProcess = nullptr; historyWindow = nullptr;
+    }
+    if (historyProcess) {
+        if (auto host = historyController(historyProcess)) {
+            AllowSetForegroundWindow(GetProcessId(historyProcess));
+            PostMessageW(host, HistoryHostShow, 0, 0);
+        }
+        return;
+    }
+    auto path = executable();
+    auto command = L"\"" + path + L"\" --history-host=" + std::to_wstring(reinterpret_cast<uintptr_t>(window));
+    STARTUPINFOW startup{sizeof(startup)};
+    startup.dwFlags = STARTF_USESHOWWINDOW; startup.wShowWindow = SW_HIDE;
+    PROCESS_INFORMATION child{};
+    if (!CreateProcessW(path.c_str(), command.data(), nullptr, nullptr, FALSE, CREATE_NO_WINDOW,
+                        nullptr, std::filesystem::path(path).parent_path().c_str(), &startup, &child))
+        throw std::runtime_error("Cannot start clipboard history window");
+    CloseHandle(child.hThread);
+    historyProcess = child.hProcess;
+    AllowSetForegroundWindow(child.dwProcessId);
+}
+void App::refreshHistoryProcess()
+{
+    if (auto host = historyController(historyProcess)) PostMessageW(host, HistoryHostRefresh, 0, 0);
+}
+void App::remoteHistory(const char *action, const std::wstring &id, bool plain)
+{
+    if (!historyService || !configurationPeer(historyService, L"KSwitcher.exe"))
+        throw std::runtime_error("KSwitcher has stopped. Reopen clipboard history.");
+    auto text = HistoryJson{{"action", action}, {"id", utf8(id)}, {"plain", plain}}.dump();
+    if (std::string_view(action) == "paste") {
+        DWORD residentPid{}; GetWindowThreadProcessId(historyService, &residentPid);
+        AllowSetForegroundWindow(residentPid);
+    }
+    COPYDATASTRUCT message{HistoryRequest, DWORD(text.size()), text.data()};
+    DWORD_PTR result{};
+    if (!SendMessageTimeoutW(historyService, WM_COPYDATA, reinterpret_cast<WPARAM>(window),
+                             reinterpret_cast<LPARAM>(&message), SMTO_ABORTIFHUNG | SMTO_ERRORONEXIT,
+                             15000, &result) || result != 1)
+        throw std::runtime_error("KSwitcher could not complete the history request. Reopen history and retry.");
+}
+LRESULT App::historyRequest(HWND sender, const COPYDATASTRUCT &message)
+{
+    DWORD pid{}; GetWindowThreadProcessId(sender, &pid);
+    if (!historyProcess || pid != GetProcessId(historyProcess) ||
+        !configurationPeer(sender, L"KSwitcher.exe") || message.cbData > 4096 ||
+        !message.cbData || !message.lpData || installingUpdate) return FALSE;
+    try {
+        const auto *first = static_cast<const char *>(message.lpData);
+        auto job = HistoryJson::parse(first, first + message.cbData);
+        auto action = job.at("action").get<std::string>();
+        auto id = wide(job.at("id").get<std::string>());
+        if (id.size() > 128) return FALSE;
+        if (action == "ready") {
+            auto ui = reinterpret_cast<HWND>(uintptr_t(std::stoull(id)));
+            DWORD uiPid{}; GetWindowThreadProcessId(ui, &uiPid);
+            wchar_t name[64]{}; GetClassNameW(ui, name, 64);
+            if (uiPid != pid || std::wstring(name) != L"KSwitcher.History") return FALSE;
+            historyWindow = ui;
+        } else if (action == "paste") {
+            if (busy || !history) return FALSE;
+            pasteEntry(id, job.at("plain").get<bool>());
+        } else if (action == "ocr") {
+            if (busy || !history) return FALSE;
+            recognizeEntry(id);
+        } else if (action == "clear") clearHistory();
+        else if (action == "pin" || action == "remove") {
+            if (busy || !history) return FALSE;
+            if (action == "pin") history->pin(id); else history->remove(id);
+        } else return FALSE;
+        return TRUE;
+    } catch (...) { return FALSE; }
+}
+void App::saveHistoryView(const std::wstring &selection, const std::wstring &top, const std::wstring &query, bool pinnedOnly)
+{
+    if (!historyService) return;
+    try {
+        auto text = HistoryJson{{"selection", utf8(selection)}, {"top", utf8(top)}, {"query", utf8(query)}, {"pinnedOnly", pinnedOnly}}.dump();
+        atomicWrite(data / L"history-view.bin", protect(Bytes(text.begin(), text.end())));
+    } catch (...) {} // Closing the UI must still release its process if state cannot be saved.
+}

src/app_sync.inl

@@ -46,7 +46,7 @@ std::wstring App::syncCommand(int action, const std::vector<SyncChoice> &choices
             syncDone.store(true);
         });
     }
-    catch (...) { syncRunning = false; throw; }
+    catch (...) { syncRunning = false; Bytes().swap(syncSnapshot); syncResult = {}; throw; }
     return syncStatus;
 }
 void App::pollSync()
@@ -57,25 +57,28 @@ void App::pollSync()
         {
             if (busy) return;
             syncWorker.join();
+            // Own completed payloads locally so every return/exception releases them.
+            auto result = std::exchange(syncResult, SyncResult{});
+            auto snapshot = std::exchange(syncSnapshot, Bytes{});
             syncRunning = false;
             syncDone = false;
-            syncStatus = syncResult.status;
-            if (syncResult.success)
+            syncStatus = result.status;
+            if (result.success)
             {
-                if (loadSyncConfig(data) != syncConnection || encodeSettings(settings) != syncSnapshot)
+                if (loadSyncConfig(data) != syncConnection || encodeSettings(settings) != snapshot)
                 {
                     syncStatus = L"Local settings or connection changed during sync. Checking again shortly.";
                     nextSync = GetTickCount64() + 2000;
                     return;
                 }
-                auto next = restoreSyncSettings(syncResult.settings, settings, layouts, syncConnection.keepLocalLayouts);
-                if (encodeSettings(next) != syncSnapshot)
+                auto next = restoreSyncSettings(result.settings, settings, layouts, syncConnection.keepLocalLayouts);
+                if (encodeSettings(next) != snapshot)
                 {
-                    atomicWrite(data / L"settings-before-sync.bin", protect(syncSnapshot));
+                    atomicWrite(data / L"settings-before-sync.bin", protect(snapshot));
                     applySettings(next);
                 }
-                saveSyncBase(data, syncConnection, syncResult.base.empty() ? syncResult.settings : syncResult.base);
-                pendingSyncConflicts = syncResult.conflicts;
+                saveSyncBase(data, syncConnection, result.base.empty() ? result.settings : result.base);
+                pendingSyncConflicts = std::move(result.conflicts);
                 conflictConnection = syncConnection;
                 SYSTEMTIME time{}; GetLocalTime(&time);
                 wchar_t stamp[32]{};
@@ -84,8 +87,8 @@ void App::pollSync()
             }
             // Back off after errors (including bad credentials) instead of repeatedly
             // hitting userpass lockout. The explicit Sync button remains available.
-            syncRetryAfter = syncResult.success ? 0 : GetTickCount64() + 15 * 60000;
-            nextSync = syncResult.success ? GetTickCount64() + SyncIntervalMs : syncRetryAfter;
+            syncRetryAfter = result.success ? 0 : GetTickCount64() + 15 * 60000;
+            nextSync = result.success ? GetTickCount64() + SyncIntervalMs : syncRetryAfter;
         }
         if (!syncRunning && GetTickCount64() >= nextSync)
         {

src/autocorrect.cpp

@@ -42,82 +42,160 @@ bool safeAutoWord(const std::wstring &word, int minimumLength)
     auto small = lower(word);
     return word == small || (word.substr(1) == small.substr(1) && word != upper(word));
 }
-std::string_view AutoCorrector::Dictionary::word(size_t index) const
+namespace {
+constexpr size_t DictionaryBlockWords = 32;
+}
+std::string_view AutoCorrector::Dictionary::word(size_t block) const
 {
-    auto start = offsets[index];
-    auto end = bytes.find('\t', start);
-    return std::string_view(bytes).substr(start, end - start);
+    size_t start = offsets[block];
+    // Every block starts with a complete word (zero shared prefix).
+    size_t length = static_cast<unsigned char>(bytes[start++]) & 15;
+    if (length == 15) length = static_cast<unsigned char>(bytes[start++]);
+    return std::string_view(bytes).substr(start, length);
 }
 AutoCorrector::Dictionary::Dictionary(const std::filesystem::path &path)
 {
-    auto raw = readFile(path, 2 * 1024 * 1024);
-    bytes.assign(raw.begin(), raw.end());
-    for (size_t start = 0; start < bytes.size();)
+    const auto raw = readFile(path, 2 * 1024 * 1024);
+    const std::string_view source(reinterpret_cast<const char *>(raw.data()), raw.size());
+    std::vector<uint32_t> lines;
+    lines.reserve(std::count(source.begin(), source.end(), '\n') + 1);
+    for (size_t start = 0; start < source.size();)
     {
-        auto end = bytes.find('\n', start);
-        if (end == bytes.npos)
-            end = bytes.size();
-        auto tab = bytes.find('\t', start);
-        if (tab == bytes.npos || tab >= end || tab == start || tab - start > 160)
+        auto end = source.find('\n', start);
+        if (end == source.npos) end = source.size();
+        auto tab = source.find('\t', start);
+        if (tab == source.npos || tab >= end || tab == start || tab - start > 160)
             throw std::runtime_error("Invalid auto-correction dictionary");
         int rank{};
-        auto rankEnd = end > tab + 1 && bytes[end - 1] == '\r' ? end - 1 : end;
-        auto parse = std::from_chars(bytes.data() + tab + 1, bytes.data() + rankEnd, rank);
-        if (parse.ec != std::errc() || parse.ptr != bytes.data() + rankEnd || rank <= 0)
+        auto rankEnd = end > tab + 1 && source[end - 1] == '\r' ? end - 1 : end;
+        auto parse = std::from_chars(source.data() + tab + 1, source.data() + rankEnd, rank);
+        if (parse.ec != std::errc() || parse.ptr != source.data() + rankEnd || rank <= 0)
             throw std::runtime_error("Invalid dictionary rank");
-        offsets.push_back((uint32_t)start);
+        lines.push_back(static_cast<uint32_t>(start));
         start = end + 1;
     }
-    if (offsets.empty())
-        throw std::runtime_error("Empty auto-correction dictionary");
-    auto entry = [&](uint32_t offset) { return std::string_view(bytes).substr(offset, bytes.find('\t', offset) - offset); };
-    auto frequency = [&](uint32_t offset)
-    {
+    if (lines.empty()) throw std::runtime_error("Empty auto-correction dictionary");
+    auto entry = [&](uint32_t offset) { return source.substr(offset, source.find('\t', offset) - offset); };
+    auto frequency = [&](uint32_t offset) {
         int rank{};
         auto start = offset + entry(offset).size() + 1;
-        std::from_chars(bytes.data() + start, bytes.data() + bytes.size(), rank);
+        std::from_chars(source.data() + start, source.data() + source.size(), rank);
         return rank;
     };
-    std::sort(offsets.begin(), offsets.end(), [&](uint32_t a, uint32_t b)
-              { return entry(a) == entry(b) ? frequency(a) < frequency(b) : entry(a) < entry(b); });
-    offsets.erase(std::unique(offsets.begin(), offsets.end(), [&](uint32_t a, uint32_t b)
-                              { return entry(a) == entry(b); }), offsets.end());
-    offsets.shrink_to_fit();
-    bytes.shrink_to_fit();
+    std::sort(lines.begin(), lines.end(), [&](uint32_t a, uint32_t b) {
+        return entry(a) == entry(b) ? frequency(a) < frequency(b) : entry(a) < entry(b);
+    });
+    lines.erase(std::unique(lines.begin(), lines.end(), [&](uint32_t a, uint32_t b) {
+        return entry(a) == entry(b);
+    }), lines.end());
+    offsets.reserve((lines.size() + DictionaryBlockWords - 1) / DictionaryBlockWords);
+    std::string_view previous;
+    // Allocate the packed payload exactly once. Geometric growth and a final
+    // shrink otherwise leave discarded buffers in the resident process heap.
+    size_t packedSize = 0;
+    for (size_t i = 0; i < lines.size(); ++i)
+    {
+        auto current = entry(lines[i]);
+        size_t prefix = 0;
+        if (i % DictionaryBlockWords != 0)
+            while (prefix < std::min(previous.size(), current.size()) && previous[prefix] == current[prefix]) ++prefix;
+        auto suffix = current.size() - prefix;
+        packedSize += 1 + (prefix >= 15) + (suffix >= 15) + suffix + 2;
+        auto rank = static_cast<uint32_t>(frequency(lines[i]));
+        if (rank >= 65535)
+            do { ++packedSize; rank >>= 7; } while (rank);
+        previous = current;
+    }
+    bytes.reserve(packedSize);
+    previous = {};
+    for (size_t i = 0; i < lines.size(); ++i)
+    {
+        auto current = entry(lines[i]);
+        size_t prefix = 0;
+        if (i % DictionaryBlockWords == 0)
+            offsets.push_back(static_cast<uint32_t>(bytes.size()));
+        else
+            while (prefix < std::min(previous.size(), current.size()) && previous[prefix] == current[prefix]) ++prefix;
+        size_t suffix = current.size() - prefix;
+        bytes.push_back(static_cast<char>((std::min(prefix, size_t(15)) << 4) | std::min(suffix, size_t(15))));
+        if (prefix >= 15) bytes.push_back(static_cast<char>(prefix));
+        if (suffix >= 15) bytes.push_back(static_cast<char>(suffix));
+        bytes.append(current.substr(prefix));
+        auto rank = static_cast<uint32_t>(frequency(lines[i]));
+        auto shortRank = std::min(rank, uint32_t(65535));
+        bytes.push_back(static_cast<char>(shortRank & 255));
+        bytes.push_back(static_cast<char>(shortRank >> 8));
+        if (rank >= 65535)
+            do {
+                auto next = rank & 127;
+                rank >>= 7;
+                bytes.push_back(static_cast<char>(next | (rank ? 128 : 0)));
+            } while (rank);
+        previous = current;
+    }
 }
 int AutoCorrector::Dictionary::rank(const std::wstring &text) const
 {
     auto key = utf8(lower(text));
     size_t begin = 0, end = offsets.size();
+    // Find the last block whose first word is <= the search key.
     while (begin < end)
     {
         auto mid = begin + (end - begin) / 2;
-        if (word(mid) < key)
-            begin = mid + 1;
-        else
-            end = mid;
+        if (word(mid) <= key) begin = mid + 1;
+        else end = mid;
     }
-    if (begin == offsets.size() || word(begin) != key)
-        return 0;
-    auto start = offsets[begin] + word(begin).size() + 1;
-    int rank{};
-    std::from_chars(bytes.data() + start, bytes.data() + bytes.size(), rank);
-    return rank;
+    if (!begin) return 0;
+    size_t block = begin - 1;
+    size_t at = offsets[block];
+    const size_t limit = begin < offsets.size() ? offsets[begin] : bytes.size();
+    char decoded[160]; // The loader validates lengths; lookup never allocates a decoded word.
+    while (at < limit)
+    {
+        auto lengths = static_cast<unsigned char>(bytes[at++]);
+        size_t prefix = lengths >> 4, suffix = lengths & 15;
+        if (prefix == 15) prefix = static_cast<unsigned char>(bytes[at++]);
+        if (suffix == 15) suffix = static_cast<unsigned char>(bytes[at++]);
+        memcpy(decoded + prefix, bytes.data() + at, suffix);
+        at += suffix;
+        uint32_t rank = static_cast<unsigned char>(bytes[at]) |
+                        (uint32_t(static_cast<unsigned char>(bytes[at + 1])) << 8);
+        at += 2;
+        if (rank == 65535) {
+            rank = 0;
+            uint32_t shift = 0;
+            unsigned char part;
+            do {
+                part = static_cast<unsigned char>(bytes[at++]);
+                rank |= uint32_t(part & 127) << shift;
+                shift += 7;
+            } while (part & 128);
+        }
+        auto compared = std::string_view(decoded, size_t(prefix) + suffix).compare(key);
+        if (compared == 0) return static_cast<int>(rank);
+        if (compared > 0) return 0;
+    }
+    return 0;
 }
 void AutoCorrector::configure(const std::filesystem::path &folder, const std::vector<std::wstring> &wanted)
 {
     if (languages == wanted)
         return;
-    std::map<std::wstring, Dictionary> next;
+    std::map<std::wstring, std::shared_ptr<const Dictionary>> next;
     for (auto &lang : wanted)
     {
         if (lang != L"en" && lang != L"uk" && lang != L"ru")
             throw std::runtime_error("Unsupported dictionary language");
-        next.emplace(lang, Dictionary(folder / (lang + L".txt")));
+        next.emplace(lang, std::make_shared<const Dictionary>(folder / (lang + L".txt")));
     }
     dictionaries = std::move(next);
     languages = wanted;
 }
+void AutoCorrector::shareDictionaries(const AutoCorrector &source)
+{
+    dictionaries = source.dictionaries;
+    languages = source.languages;
+}
 void AutoCorrector::reject(std::wstring word, const Settings &settings)
 {
     while (!word.empty() && openingDelimiter(word.front(), settings))
@@ -132,7 +210,7 @@ size_t AutoCorrector::memoryBytes() const
 {
     size_t bytes = 0;
     for (auto &[language, d] : dictionaries)
-        bytes += d.bytes.capacity() + d.offsets.capacity() * sizeof(uint32_t);
+        bytes += d->bytes.capacity() + d->offsets.capacity() * sizeof(uint32_t);
     return bytes;
 }
 std::optional<AutoSuggestion> AutoCorrector::suggest(const std::wstring &typed, int source,
@@ -191,7 +269,7 @@ std::optional<AutoSuggestion> AutoCorrector::suggest(const std::wstring &typed,
     };
     // Valid words from either selected language are never changed.
     for (auto &[language, d] : dictionaries)
-        if (d.rank(word) || personal(language, word))
+        if (d->rank(word) || personal(language, word))
             return {};
     std::optional<AutoSuggestion> candidate;
     std::optional<std::wstring> matchedText;
@@ -211,7 +289,7 @@ std::optional<AutoSuggestion> AutoCorrector::suggest(const std::wstring &typed,
         auto converted = convert(word, layouts[source], layouts[i], true);
         if (converted == word || !safeAutoWord(converted, settings.autoMinLength))
             continue;
-        int rank = personal(dictionary->first, converted) ? 1 : dictionary->second.rank(converted);
+        int rank = personal(dictionary->first, converted) ? 1 : dictionary->second->rank(converted);
         if (!rank)
             continue;
         if (matchedText && *matchedText != converted)
@@ -233,7 +311,7 @@ std::optional<AutoSuggestion> AutoCorrector::suggest(const std::wstring &typed,
     auto consider = [&](const std::wstring &text)
     {
         if (text == small || text == found || text.size() < 4 || text.size() > 32) return true;
-        int rank = personalTargets.contains(text) ? 1 : dictionaries.at(sourceLanguage).rank(text);
+        int rank = personalTargets.contains(text) ? 1 : dictionaries.at(sourceLanguage)->rank(text);
         if (!rank) return true;
         if (!found.empty()) return false;
         found = text;

src/autocorrect.h

@@ -1,6 +1,7 @@
 #pragma once
 #include "platform.h"
 #include <map>
+#include <memory>
 #include <set>
 #include <string_view>
 namespace ks
@@ -18,23 +19,30 @@ int matchAutoInput(const Run &, const std::wstring &, const std::vector<Layout>
 bool autoCorrectionAllowed(HWND, const Settings &);
 class AutoCorrector
 {
+    friend struct AutoCorrectorRegressionAccess;
     struct Dictionary
     {
+        // Front-coded UTF-8 words in independently searchable blocks of 32.
+        // Prefix/suffix lengths share a byte (15 escapes to a full byte length).
+        // Ranks use two bytes; 65535 escapes to a varint for larger custom ranks.
         std::string bytes;
         std::vector<uint32_t> offsets;
         std::string_view word(size_t) const;
         explicit Dictionary(const std::filesystem::path &);
         int rank(const std::wstring &) const;
     };
-    std::map<std::wstring, Dictionary> dictionaries;
+    std::map<std::wstring, std::shared_ptr<const Dictionary>> dictionaries;
     std::vector<std::wstring> languages;
     std::set<std::wstring> rejected;
 
   public:
     void configure(const std::filesystem::path &, const std::vector<std::wstring> &);
+    // Share immutable dictionary storage, keeping each consumer's undo rejections private.
+    void shareDictionaries(const AutoCorrector &);
     std::optional<AutoSuggestion> suggest(const std::wstring &, int source, const std::vector<Layout> &,
                                           const Settings &) const;
     void reject(std::wstring word, const Settings & = {});
+    // Referenced dictionary payload, including shared storage (do not sum across consumers).
     size_t memoryBytes() const;
 };
 } // namespace ks

src/config_main.cpp

@@ -79,7 +79,7 @@ LRESULT CALLBACK controller(HWND window, UINT message, WPARAM wp, LPARAM lp)
 }
 // The configurator owns no history store, dictionaries, worker or input hooks.
 // All mutations are validated and committed by the resident process.
-App::App(HINSTANCE h, bool, const std::filesystem::path &) : instance(h)
+App::App(HINSTANCE h, bool, const std::filesystem::path &, HWND) : instance(h)
 {
     current = this;
     data = dataDirectory();

src/history_preview.h

@@ -4,14 +4,28 @@
 #include <string>
 
 namespace ks {
+inline constexpr size_t HistoryThumbnailBudget = 1024 * 1024;
+inline constexpr size_t HistoryRichTextBudget = 256 * 1024;
 // Keep the visible working set even in unusually tall windows. Never evict a
 // visible preview to admit another visible preview: that creates a paint loop.
+template<class T, class Weight>
+void trimHistoryPreviews(std::map<std::wstring,T> &cache,
+                         const std::set<std::wstring> &visible, size_t limit,
+                         size_t byteLimit, Weight weight)
+{
+    size_t bytes = 0;
+    for (const auto &[id, value] : cache) bytes += weight(value);
+    for(auto it=cache.begin(); (cache.size()>limit || bytes>byteLimit) && it!=cache.end();)
+        if(!visible.contains(it->first)) {
+            bytes -= weight(it->second);
+            it=cache.erase(it);
+        }
+        else ++it;
+}
 template<class T>
 void trimHistoryPreviews(std::map<std::wstring,T> &cache,
                          const std::set<std::wstring> &visible, size_t limit=32)
 {
-    for(auto it=cache.begin(); cache.size()>limit && it!=cache.end();)
-        if(!visible.contains(it->first)) it=cache.erase(it);
-        else ++it;
+    trimHistoryPreviews(cache, visible, limit, 0, [](const T &) { return size_t{}; });
 }
 }

src/main.cpp

@@ -1,12 +1,27 @@
 #include "app.h"
 #include <shellapi.h>
 #include <shlobj.h>
+#include "configuration.h"
 int WINAPI wWinMain(HINSTANCE instance, HINSTANCE, PWSTR, int)
 {
     CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED);
     int argc{};
     auto argv = CommandLineToArgvW(GetCommandLineW(), &argc);
     std::wstring arg = argc > 1 ? argv[1] : L"";
+    if (argc == 2 && arg.starts_with(L"--history-host=")) {
+        LocalFree(argv);
+        int result = 1;
+        try {
+            auto service = reinterpret_cast<HWND>(uintptr_t(std::stoull(arg.substr(15))));
+            wchar_t name[64]{}; GetClassNameW(service, name, 64);
+            if (std::wstring(name) != L"KSwitcher.Main" || !ks::configurationPeer(service, L"KSwitcher.exe"))
+                throw std::runtime_error("Invalid history service");
+            ks::App app(instance, true, {}, service);
+            result = app.execute();
+        } catch (...) {}
+        CoUninitialize();
+        return result;
+    }
     if (arg.starts_with(L"--configure-autostart="))
     {
         int result = 1;
@@ -72,6 +87,7 @@ int WINAPI wWinMain(HINSTANCE instance, HINSTANCE, PWSTR, int)
     try
     {
         ks::App app(instance, arg == L"--smoke-test");
+        app.isolateHistory = !app.smoke;
         if (arg.starts_with(L"--update-ready-event="))
             app.updateStartupEvent = arg.substr(std::wstring(L"--update-ready-event=").size());
         else if (!arg.empty() && arg != L"--smoke-test")

src/ocr.cpp

@@ -123,13 +123,16 @@ struct OcrStatics : IInspectable
 Pixels decodeImage(const Clip &clip, UINT maxWidth, UINT maxHeight)
 {
     Bytes encoded;
+    const Bytes *input = &encoded;
     for (const auto &f : clip.formats)
         if (f.name == L"PNG")
         {
-            encoded = f.data;
+            input = &f.data;
             break;
         }
-    if (encoded.empty())
+    if (input->empty())
+    {
+        input = &encoded;
         for (const auto &f : clip.formats)
             if ((f.id == CF_DIB || f.id == CF_DIBV5) && f.data.size() >= 40)
             {
@@ -146,19 +149,21 @@ Pixels decodeImage(const Clip &clip, UINT maxWidth, UINT maxHeight)
                 file.bfType = 0x4d42;
                 file.bfSize = (DWORD)(sizeof(file) + f.data.size());
                 file.bfOffBits = (DWORD)offset;
-                encoded.resize(sizeof(file));
+                encoded.resize(sizeof(file) + f.data.size());
                 memcpy(encoded.data(), &file, sizeof(file));
-                encoded.insert(encoded.end(), f.data.begin(), f.data.end());
+                memcpy(encoded.data() + sizeof(file), f.data.data(), f.data.size());
                 break;
             }
-    if (encoded.empty())
+    }
+    if (input->empty())
         throw std::runtime_error("This clipboard item has no supported image");
     Com<IWICImagingFactory> wic;
     check(CoCreateInstance(CLSID_WICImagingFactory, nullptr, CLSCTX_INPROC_SERVER, IID_IWICImagingFactory,
                            (void **)wic.out()));
     Com<IWICStream> stream;
     check(wic->CreateStream(stream.out()));
-    check(stream->InitializeFromMemory(encoded.data(), (DWORD)encoded.size()));
+    // WIC decoding only reads the stream. The clip outlives every WIC object here.
+    check(stream->InitializeFromMemory(const_cast<BYTE *>(input->data()), (DWORD)input->size()));
     Com<IWICBitmapDecoder> decoder;
     check(wic->CreateDecoderFromStream(stream.p, nullptr, WICDecodeMetadataCacheOnLoad, decoder.out()));
     Com<IWICBitmapFrameDecode> frame;

src/paste_probe.h

@@ -13,7 +13,7 @@ class PasteProbe
 
   public:
     std::wstring status = L"not-requested";
-    PasteProbe(bool enabled, const std::wstring &original)
+    PasteProbe(bool enabled, HWND target)
     {
         if (!enabled)
             return;
@@ -25,6 +25,18 @@ class PasteProbe
         automation->put_TransactionTimeout(200);
         if (FAILED(automation->GetFocusedElement(&element)) || !element)
             return;
+        if (target)
+        {
+            DWORD process{};
+            GetWindowThreadProcessId(target, &process);
+            int focusedProcess{};
+            if (!process || FAILED(element->get_CurrentProcessId(&focusedProcess)) ||
+                process != static_cast<DWORD>(focusedProcess) || GetForegroundWindow() != target)
+            {
+                status = L"focused-control-changed";
+                return;
+            }
+        }
         BOOL password = TRUE;
         if (FAILED(element->get_CurrentIsPassword(&password)) || password)
         {
@@ -35,6 +47,11 @@ class PasteProbe
                                                 (void **)&pattern)) ||
             !pattern)
             return;
+    }
+    PasteProbe(bool enabled, const std::wstring &original, HWND target = nullptr)
+        : PasteProbe(enabled, target)
+    {
+        if (!pattern) return;
         auto selected = read(1, false);
         auto normalize = [](std::wstring value)
         {

src/platform.cpp

@@ -159,6 +159,31 @@ void showRequestedWindow(HWND window)
     if (!IsWindowVisible(window))
         ShowWindow(window, SW_SHOW);
 }
+void showMenuAccessKeys(HMENU menu)
+{
+    // Mouse-opened popups ignore the owner's keyboard-cue state.
+    // Preserve the mnemonic and expose it in the right-hand hint column.
+    for (int i = 0; i < GetMenuItemCount(menu); ++i)
+    {
+        if (auto child = GetSubMenu(menu, i)) showMenuAccessKeys(child);
+        int length = GetMenuStringW(menu, i, nullptr, 0, MF_BYPOSITION);
+        std::wstring text(length + 1, L'\0');
+        GetMenuStringW(menu, i, text.data(), (int)text.size(), MF_BYPOSITION);
+        text.resize(length);
+        if (text.find(L'\t') != text.npos) continue;
+        for (size_t p = 0; p + 1 < text.size(); ++p)
+        {
+            if (text[p] != L'&') continue;
+            if (text[p + 1] == L'&') { ++p; continue; }
+            text += L"\t" + upper(text.substr(p + 1, 1));
+            MENUITEMINFOW item{sizeof(item)};
+            item.fMask = MIIM_STRING;
+            item.dwTypeData = text.data();
+            SetMenuItemInfoW(menu, i, TRUE, &item);
+            break;
+        }
+    }
+}
 bool activateWindow(HWND window)
 {
     if (!IsWindow(window))
@@ -240,15 +265,27 @@ std::wstring processName(HWND window)
     CloseHandle(h);
     return ok ? std::filesystem::path(std::wstring(path, n)).stem().wstring() : L"";
 }
-Clip readClipboard(HWND window, size_t limit)
+Clip readClipboard(HWND window, size_t limit, ClipboardRead mode, std::optional<DWORD> expected)
 {
     ClipboardLock lock(window);
+    if (expected && *expected != GetClipboardSequenceNumber())
+        throw std::runtime_error("Clipboard changed while taking snapshot");
+    if (mode == ClipboardRead::WithoutImages &&
+        (IsClipboardFormatAvailable(CF_DIB) || IsClipboardFormatAvailable(CF_DIBV5) ||
+         IsClipboardFormatAvailable(CF_BITMAP) || IsClipboardFormatAvailable(RegisterClipboardFormatW(L"PNG"))))
+        throw std::runtime_error("Clipboard changed to an image");
     Clip c;
     size_t total = 0;
     for (UINT f = EnumClipboardFormats(0); f; f = EnumClipboardFormats(f))
     {
         if (!globalFormat(f))
             continue;
+        wchar_t name[256]{};
+        if (f >= 0xc000) GetClipboardFormatNameW(f, name, 256);
+        if (mode == ClipboardRead::Selection && f != CF_UNICODETEXT &&
+            std::wstring_view(name) != L"VisualStudioEditorOperationsLineCutCopyClipboardTag" &&
+            std::wstring_view(name) != L"MSDEVLineSelect" && std::wstring_view(name) != L"vscode-editor-data")
+            continue;
         HANDLE handle = GetClipboardData(f);
         if (!handle)
             continue;
@@ -266,8 +303,6 @@ Clip readClipboard(HWND window, size_t limit)
         GlobalUnlock(handle);
         if (f >= 0xc000)
         {
-            wchar_t name[256]{};
-            GetClipboardFormatNameW(f, name, 256);
             format.name = name;
         }
         total += size;
@@ -275,7 +310,8 @@ Clip readClipboard(HWND window, size_t limit)
     }
     return c;
 }
-DWORD writeClipboard(HWND window, const Clip &c)
+DWORD writeClipboard(HWND window, const Clip &c) { return writeClipboardGuarded(window, c, {}); }
+DWORD writeClipboardGuarded(HWND window, const Clip &c, std::optional<DWORD> expected)
 {
     // Allocate all blocks before replacing any existing data.
     std::vector<std::pair<UINT, HGLOBAL>> blocks;
@@ -302,6 +338,8 @@ DWORD writeClipboard(HWND window, const Clip &c)
             blocks.emplace_back(id, h);
         }
         ClipboardLock lock(window);
+        if (expected && *expected != GetClipboardSequenceNumber())
+            throw std::runtime_error("Clipboard changed before restoring snapshot");
         if (!EmptyClipboard())
             throw std::runtime_error("Cannot replace clipboard");
         for (auto &[id, h] : blocks)
@@ -579,10 +617,25 @@ std::recursive_mutex logGate;
 bool loggingEnabled = false;
 DiagnosticBuffer diagnosticBuffer;
 }
+size_t DiagnosticBuffer::expire(ULONGLONG now)
+{
+    size_t removed = 0;
+    while (!entries.empty() && now - entries.front().first > 30000)
+    {
+        entries.pop_front();
+        ++removed;
+    }
+    return removed;
+}
+void expireDiagnostics(ULONGLONG now)
+{
+    std::lock_guard lock(logGate);
+    diagnosticBuffer.expire(now);
+}
 std::wstring DiagnosticBuffer::record(const std::wstring &message, bool problem, ULONGLONG now)
 {
-    while (!entries.empty() && (entries.size() >= 128 || now - entries.front().first > 30000))
-        entries.pop_front();
+    expire(now);
+    while (entries.size() >= 128) entries.pop_front();
     entries.emplace_back(now, message);
     if (!problem)
         return {};

src/platform.h

@@ -38,12 +38,16 @@ HKL windowLayout(HWND);
 bool switchWindowLayout(HWND, HKL, const std::function<bool()> &valid);
 bool activateWindow(HWND);
 void showRequestedWindow(HWND);
+void showMenuAccessKeys(HMENU);
 bool ownsClipboard(HWND);
 bool webViewDescendant(DWORD owner, DWORD host,
                        const std::function<std::optional<std::pair<DWORD, std::wstring>>(DWORD)> &read);
 std::wstring processName(HWND);
-Clip readClipboard(HWND, size_t limit = 32 * 1024 * 1024);
+enum class ClipboardRead { All, Selection, WithoutImages };
+Clip readClipboard(HWND, size_t limit = 32 * 1024 * 1024,
+                   ClipboardRead = ClipboardRead::All, std::optional<DWORD> expected = {});
 DWORD writeClipboard(HWND, const Clip &);
+DWORD writeClipboardGuarded(HWND, const Clip &, std::optional<DWORD> expected);
 Clip textClip(const std::wstring &);
 bool chord(WORD key, UINT modifiers = 0);
 // Process-local marker, shared by every KSwitcher input producer (not an authentication token).
@@ -71,10 +75,12 @@ class DiagnosticBuffer
 {
     std::deque<std::pair<ULONGLONG, std::wstring>> entries;
   public:
+    size_t expire(ULONGLONG now);
     std::wstring record(const std::wstring &message, bool problem, ULONGLONG now);
     void clear() { entries.clear(); }
 };
 void setLoggingEnabled(bool enabled);
+void expireDiagnostics(ULONGLONG now);
 void diagnosticEvent(const std::wstring &message, bool problem = false);
 void diagnosticOperation(const std::string &json);
 std::wstring readDiagnosticLog(bool previous);

src/richtext.cpp

@@ -252,7 +252,7 @@ DWORD CALLBACK readStream(DWORD_PTR cookie, LPBYTE buffer, LONG size, LONG *read
     return 0;
 }
 } // namespace
-std::string richPreview(const Clip &clip)
+std::string richPreview(const Clip &clip, bool plainFallback)
 {
     for (const auto &f : clip.formats)
         if (f.name == L"Rich Text Format" && f.data.size() <= 65536)
@@ -276,6 +276,7 @@ std::string richPreview(const Clip &clip)
             {
             }
         }
+    if (!plainFallback) return {};
     auto text = clip.text();
     if (text.size() > 4096)
         text.resize(4096);

src/richtext.h

@@ -2,7 +2,7 @@
 #include "platform.h"
 namespace ks
 {
-std::string richPreview(const Clip &);
+std::string richPreview(const Clip &, bool plainFallback = true);
 HWND createRichText(HWND parent, int id, bool visible);
 bool setRichText(HWND, const std::string &);
 } // namespace ks

src/screenshot.cpp

@@ -783,12 +783,13 @@ HCURSOR actionCursor(const Capture &c,std::pair<int,MarkPart> hit,bool inside)
     if(hit.second==MarkPart::Body || hit.second==MarkPart::Label) cursor=IDC_SIZEALL;
     else if(hit.second==MarkPart::Rotation) cursor=IDC_HAND;
     else if(hit.second>=MarkPart::Vertex0 && hit.second<=MarkPart::Vertex2) cursor=IDC_SIZEALL;
-    else if(hit.second==MarkPart::Radius) cursor=IDC_SIZEWE;
-    else if(hit.second==MarkPart::Start || hit.second==MarkPart::End || hit.second==MarkPart::Thickness) {
+    else if(hit.second==MarkPart::Start || hit.second==MarkPart::End || hit.second==MarkPart::Radius)
+        cursor=IDC_SIZEALL;
+    else if(hit.second==MarkPart::Thickness) {
         const auto &mark=c.marks[hit.first];
-        auto [from,to]=hit.second==MarkPart::Thickness?thicknessSegment(mark):std::pair{mark.from,mark.to};
+        auto [from,to]=thicknessSegment(mark);
         double angle=std::atan2(double(to.y-from.y),double(to.x-from.x));
-        if(hit.second==MarkPart::Thickness) angle+=3.141592653589793/2;
+        angle+=3.141592653589793/2;
         int axis=(int(std::lround(angle/(3.141592653589793/4)))+8)%4;
         const LPCWSTR cursors[]{IDC_SIZEWE,IDC_SIZENWSE,IDC_SIZENS,IDC_SIZENESW};
         cursor=cursors[axis];

src/screenshot_activation.cpp

@@ -50,6 +50,30 @@ void registerScreenshotNotifications()
     // Notify the shell that notification identity/activation registration changed.
     SHChangeNotify(SHCNE_ASSOCCHANGED,SHCNF_IDLIST,nullptr,nullptr);
 }
+HANDLE startScreenshotNotificationRegistration()
+{
+    auto path=std::filesystem::path(executable()).parent_path()/L"KSwitcher.Screenshot.exe";
+    auto command=L"\""+path.wstring()+L"\" --register-notifications";
+    STARTUPINFOW startup{sizeof(startup)};
+    startup.dwFlags=STARTF_USESHOWWINDOW; startup.wShowWindow=SW_HIDE;
+    PROCESS_INFORMATION process{};
+    if(!CreateProcessW(path.c_str(),command.data(),nullptr,nullptr,FALSE,CREATE_NO_WINDOW,
+                       nullptr,path.parent_path().c_str(),&startup,&process))
+        throw std::runtime_error(utf8(lastError(L"Cannot start notification registration helper")));
+    CloseHandle(process.hThread);
+    return process.hProcess;
+}
+void registerScreenshotNotificationsInHelper()
+{
+    auto process=startScreenshotNotificationRegistration();
+    auto wait=WaitForSingleObject(process,10000);
+    DWORD code=ERROR_GEN_FAILURE;
+    bool completed=wait==WAIT_OBJECT_0 && GetExitCodeProcess(process,&code);
+    CloseHandle(process);
+    if(!completed || code)
+        throw std::runtime_error(completed ? "Notification registration helper failed: "+std::to_string(code)
+                                          : "Notification registration helper did not complete within 10 seconds");
+}
 bool validScreenshotToken(const std::wstring &id)
 {
     if(id.size()!=36) return false;

src/screenshot_main.cpp

@@ -1,5 +1,6 @@
 #include "screenshot.h"
 #include "screenshot_notifications.h"
+#include "storage.h"
 #include <commctrl.h>
 #include <shellapi.h>
 #include <roapi.h>
@@ -49,6 +50,18 @@ int WINAPI wWinMain(HINSTANCE instance,HINSTANCE,PWSTR,int)
     std::wstring token;
     bool autoOpenEditor=false, writeLog=false;
     int argc{}; auto argv=CommandLineToArgvW(GetCommandLineW(),&argc);
+    if(argc==3 && std::wstring(argv[1])==L"--clipboard-snapshot") {
+        std::filesystem::path request=argv[2]; LocalFree(argv);
+        return ks::runClipboardSnapshot(request);
+    }
+    if(argc==3 && (std::wstring(argv[1])==L"--capture-history" || std::wstring(argv[1])==L"--history-ocr")) {
+        bool ocr=std::wstring(argv[1])==L"--history-ocr";
+        std::filesystem::path request=argv[2]; LocalFree(argv);
+        auto initialized=CoInitializeEx(nullptr,COINIT_MULTITHREADED);
+        if(FAILED(initialized)) return 1;
+        int result=ocr ? ks::runHistoryOcr(request) : ks::runImageHistoryCapture(request);
+        CoUninitialize(); return result;
+    }
     if(argc>1 && std::wstring(argv[argc-1])==L"--write-log") {
         writeLog=true; --argc;
         ks::setLoggingEnabled(true);

src/screenshot_notifications.cpp

@@ -206,7 +206,7 @@ bool notifyUpdateAvailable(const std::wstring &version)
 {
     try {
         // Reuse the screenshot notification identity, Windows settings and COM activator.
-        registerScreenshotNotifications();
+        registerScreenshotNotificationsInHelper();
         ComPtr<Notifications::IToastNotificationManagerStatics> manager;
         String managerClass(L"Windows.UI.Notifications.ToastNotificationManager");
         check(RoGetActivationFactory(managerClass.value,IID_PPV_ARGS(&manager)));

src/screenshot_notifications.h

@@ -4,6 +4,10 @@ namespace ks {
 bool notifyScreenshot(const Clip &);
 std::string screenshotNotificationError();
 void registerScreenshotNotifications();
+// Caller owns the returned process handle; the helper exits after registration.
+HANDLE startScreenshotNotificationRegistration();
+// For background notification workers only; bounded wait, never on the UI thread.
+void registerScreenshotNotificationsInHelper();
 int runScreenshotToastActivator();
 DWORD startScreenshotActivationListener();
 bool validScreenshotToken(const std::wstring &);

src/storage.cpp

@@ -4,6 +4,7 @@
 #include <algorithm>
 #include <set>
 #include <sstream>
+#include <wincrypt.h>
 
 namespace ks
 {
@@ -374,9 +375,17 @@ Clip decodeClip(const Bytes &b)
 History::History(const std::filesystem::path &folder) : folder_(folder)
 {
     std::filesystem::create_directories(folder_);
+    loadIndex();
+}
+void History::loadIndex()
+{
+    std::vector<Entry> loaded;
     auto index = folder_ / L"index.dat";
     if (!std::filesystem::exists(index))
+    {
+        entries_.clear();
         return;
+    }
     auto j = parse(unprotect(readFile(index, 16 * 1024 * 1024)));
     if (!j.is_array() || j.size() > 10000)
         throw std::runtime_error("Invalid history index");
@@ -391,8 +400,169 @@ History::History(const std::filesystem::path &folder) : folder_(folder)
                    e.value("image", false),
                    e.value("files", false), e.value("ocrState", e.value("image", false) ? 1 : 0),
                    str(e, "ocrProfile", L"windows")};
+        if (e.value("fingerprintVersion", 0) == 1) {
+            item.contentHash = e.value("contentHash", std::string{});
+            item.imageHash = e.value("imageHash", std::string{});
+            item.pixelHash = e.value("pixelHash", std::string{});
+        }
         if (validId(item.id) && std::filesystem::exists(folder_ / (item.id + L".dat")))
-            entries_.push_back(std::move(item));
+            loaded.push_back(std::move(item));
+    }
+    entries_ = std::move(loaded);
+}
+void History::reload() { std::lock_guard lock(mutex_); loadIndex(); }
+void ClipboardSnapshot::cleanup() noexcept
+{
+    if (request_.empty()) return;
+    std::error_code ignored;
+    for (const auto *suffix : {L"", L".snapshot", L".result"})
+        std::filesystem::remove(std::filesystem::path(request_.wstring() + suffix), ignored);
+    request_.clear();
+}
+ClipboardSnapshot::~ClipboardSnapshot() { cleanup(); }
+DWORD ClipboardSnapshot::run(bool restore, DWORD sequence)
+{
+    atomicWrite(request_, protect(jsonBytes(Json{{"schema", 1}, {"restore", restore}, {"sequence", sequence}})));
+    auto helper = std::filesystem::path(executable()).parent_path() / L"KSwitcher.Screenshot.exe";
+    auto command = L"\"" + helper.wstring() + L"\" --clipboard-snapshot \"" + request_.wstring() + L"\"";
+    STARTUPINFOW startup{sizeof(startup)};
+    startup.dwFlags = STARTF_USESHOWWINDOW; startup.wShowWindow = SW_HIDE;
+    PROCESS_INFORMATION process{};
+    if (!CreateProcessW(helper.c_str(), command.data(), nullptr, nullptr, FALSE, CREATE_NO_WINDOW,
+                        nullptr, helper.parent_path().c_str(), &startup, &process))
+        throw std::runtime_error("Cannot start clipboard snapshot helper");
+    CloseHandle(process.hThread);
+    auto wait = WaitForSingleObject(process.hProcess, 10000);
+    DWORD result = ERROR_GEN_FAILURE;
+    if (wait != WAIT_OBJECT_0)
+    {
+        TerminateProcess(process.hProcess, ERROR_TIMEOUT);
+        WaitForSingleObject(process.hProcess, INFINITE);
+    }
+    GetExitCodeProcess(process.hProcess, &result);
+    CloseHandle(process.hProcess);
+    if (wait != WAIT_OBJECT_0 || result) throw std::runtime_error("Clipboard snapshot helper failed");
+    return parse(unprotect(readFile(request_.wstring() + L".result", 4096))).at("sequence").get<DWORD>();
+}
+void ClipboardSnapshot::capture(HWND window, DWORD sequence)
+{
+    cleanup();
+    clip_ = {};
+    if (!IsClipboardFormatAvailable(CF_DIB) && !IsClipboardFormatAvailable(CF_DIBV5) &&
+        !IsClipboardFormatAvailable(CF_BITMAP) && !IsClipboardFormatAvailable(RegisterClipboardFormatW(L"PNG")))
+    {
+        clip_ = readClipboard(window, 64 * 1024 * 1024, ClipboardRead::WithoutImages, sequence);
+        return;
+    }
+    request_ = std::filesystem::temp_directory_path() / (L"ks-clipboard-" + newSnippetId() + L".request");
+    try { run(false, sequence); }
+    catch (...) { cleanup(); throw; }
+}
+DWORD ClipboardSnapshot::restore(HWND window, DWORD sequence)
+{
+    return request_.empty() ? writeClipboardGuarded(window, clip_, sequence) : run(true, sequence);
+}
+int runClipboardSnapshot(const std::filesystem::path &request)
+{
+    try
+    {
+        if (!request.is_absolute() || !request.filename().wstring().starts_with(L"ks-clipboard-") ||
+            request.extension() != L".request") return 1;
+        auto job = parse(unprotect(readFile(request, 4096)));
+        if (job.at("schema") != 1) return 1;
+        auto sequence = job.at("sequence").get<DWORD>();
+        const auto snapshot = request.wstring() + L".snapshot";
+        if (job.at("restore").get<bool>())
+        {
+            auto clip = decodeClip(unprotect(readFile(snapshot, 70 * 1024 * 1024)));
+            HWND window = CreateWindowExW(0, L"STATIC", L"", 0, 0, 0, 0, 0, HWND_MESSAGE, nullptr, nullptr, nullptr);
+            if (!window) return 1;
+            struct WindowCleanup { HWND window; ~WindowCleanup() { DestroyWindow(window); } } cleanup{window};
+            sequence = writeClipboardGuarded(window, clip, sequence);
+        }
+        else
+        {
+            auto clip = readClipboard(nullptr, 64 * 1024 * 1024, ClipboardRead::All, sequence);
+            if (sequence != GetClipboardSequenceNumber()) return 2;
+            atomicWrite(snapshot, protect(encodeClip(clip)));
+        }
+        atomicWrite(request.wstring() + L".result", protect(jsonBytes(Json{{"sequence", sequence}})));
+        return 0;
+    }
+    catch (...) { return 1; }
+}
+bool History::captureImage(DWORD sequence, const std::wstring &app, const Settings &settings)
+{
+    // Serialize helper index changes with all resident history mutations. Only
+    // metadata is reloaded: GetClipboardData's image allocations die with the child.
+    std::lock_guard lock(mutex_);
+    if (sequence != GetClipboardSequenceNumber()) return false;
+    auto request = std::filesystem::absolute(folder_) / (L"capture-" + newSnippetId() + L".request");
+    struct Cleanup {
+        std::filesystem::path path;
+        ~Cleanup() { std::error_code ignored; std::filesystem::remove(path, ignored); }
+    } cleanup{request};
+    Json job{{"schema", 1}, {"sequence", sequence}, {"app", utf8(app)},
+             {"settings", Json::parse(encodeSettings(settings))}};
+    atomicWrite(request, protect(jsonBytes(job)));
+    auto helper = std::filesystem::path(executable()).parent_path() / L"KSwitcher.Screenshot.exe";
+    auto command = L"\"" + helper.wstring() + L"\" --capture-history \"" + request.wstring() + L"\"";
+    STARTUPINFOW startup{sizeof(startup)};
+    startup.dwFlags = STARTF_USESHOWWINDOW; startup.wShowWindow = SW_HIDE;
+    PROCESS_INFORMATION process{};
+    if (!CreateProcessW(helper.c_str(), command.data(), nullptr, nullptr, FALSE, CREATE_NO_WINDOW,
+                        nullptr, helper.parent_path().c_str(), &startup, &process))
+        throw std::runtime_error(utf8(lastError(L"Cannot start image history helper")));
+    CloseHandle(process.hThread);
+    auto wait = WaitForSingleObject(process.hProcess, 30000);
+    DWORD result = ERROR_GEN_FAILURE;
+    if (wait != WAIT_OBJECT_0)
+    {
+        // Never release the index lock while a timed-out child can still write it.
+        TerminateProcess(process.hProcess, ERROR_TIMEOUT);
+        WaitForSingleObject(process.hProcess, INFINITE);
+    }
+    GetExitCodeProcess(process.hProcess, &result);
+    CloseHandle(process.hProcess);
+    loadIndex(); // Also reconcile any completed atomic save before a child failure.
+    if (wait != WAIT_OBJECT_0) throw std::runtime_error("Image history helper timed out");
+    if (result == 2) return false;
+    if (result == 3) throw std::runtime_error("Clipboard exceeds the configured size limit");
+    if (result) throw std::runtime_error("Image history helper failed: " + std::to_string(result));
+    return true;
+}
+int runImageHistoryCapture(const std::filesystem::path &request)
+{
+    try
+    {
+        if (!request.is_absolute() || !request.filename().wstring().starts_with(L"capture-") ||
+            request.extension() != L".request") return 1;
+        auto job = parse(unprotect(readFile(request, 4 * 1024 * 1024)));
+        if (job.at("schema") != 1) return 1;
+        auto sequence = job.at("sequence").get<DWORD>();
+        auto settings = decodeSettings(jsonBytes(job.at("settings")), readLayouts());
+        auto valid = [&] {
+            return settings.history && sequence == GetClipboardSequenceNumber() &&
+                !IsClipboardFormatAvailable(RegisterClipboardFormatW(L"ExcludeClipboardContentFromMonitorProcessing")) &&
+                !IsClipboardFormatAvailable(RegisterClipboardFormatW(L"Clipboard Viewer Ignore"));
+        };
+        if (!valid()) return 2;
+        if (!IsClipboardFormatAvailable(CF_DIB) && !IsClipboardFormatAvailable(CF_DIBV5) &&
+            !IsClipboardFormatAvailable(CF_BITMAP) &&
+            !IsClipboardFormatAvailable(RegisterClipboardFormatW(L"PNG"))) return 2;
+        auto clip = readClipboard(nullptr, size_t(settings.maxImageMiB) * 1024 * 1024);
+        if (!valid()) return 2;
+        for (const auto &format : clip.formats)
+            if (format.name == L"CanIncludeInClipboardHistory" && format.data.size() >= 4 &&
+                !format.data[0] && !format.data[1] && !format.data[2] && !format.data[3]) return 2;
+        History history(request.parent_path());
+        if (!valid()) return 2;
+        history.add(clip, str(job, "app"), settings);
+        return 0;
+    }
+    catch (const std::exception &e)
+    {
+        return std::string(e.what()) == "Clipboard exceeds the configured size limit" ? 3 : 1;
     }
 }
 void History::saveIndex()
@@ -406,7 +576,9 @@ void History::saveIndex()
                      {"at", e.at},
                      {"pinned", e.pinned},
                      {"image", e.image},
-                     {"files", e.files}, {"ocrState", e.ocrState}, {"ocrProfile", utf8(e.ocrProfile)}});
+                     {"files", e.files}, {"ocrState", e.ocrState}, {"ocrProfile", utf8(e.ocrProfile)},
+                     {"fingerprintVersion", 1}, {"contentHash", e.contentHash},
+                     {"imageHash", e.imageHash}, {"pixelHash", e.pixelHash}});
     atomicWrite(folder_ / L"index.dat", protect(jsonBytes(j)));
 }
 std::vector<Entry> History::entries() const
@@ -439,12 +611,10 @@ void History::prune(const Settings &s)
         entries_.erase(entries_.begin() + i);
     }
 }
-bool sameClipboardImage(const Clip &a, const Clip &b)
+static const Format *clipboardImageFormat(const Clip &c)
 {
     // OLE DataObject / Ole Private Data change when Snipping Tool republishes
     // the same capture. They are transport metadata, not image identity.
-    auto image = [](const Clip &c) -> const Format *
-    {
         if (!c.text().empty())
             return nullptr;
         for (const auto &f : c.formats)
@@ -458,8 +628,42 @@ bool sameClipboardImage(const Clip &a, const Clip &b)
                 if (f.id == id && !f.data.empty())
                     return &f;
         return nullptr;
-    };
-    const auto *left = image(a), *right = image(b);
+}
+static std::string clipboardHash(const Bytes &bytes)
+{
+    struct Hash {
+        HCRYPTPROV provider{}; HCRYPTHASH hash{};
+        ~Hash() { if (hash) CryptDestroyHash(hash); if (provider) CryptReleaseContext(provider, 0); }
+    } state;
+    if (!CryptAcquireContextW(&state.provider, nullptr, nullptr, PROV_RSA_AES, CRYPT_VERIFYCONTEXT) ||
+        !CryptCreateHash(state.provider, CALG_SHA_256, 0, 0, &state.hash) ||
+        !CryptHashData(state.hash, bytes.data(), static_cast<DWORD>(bytes.size()), 0))
+        throw std::runtime_error("Cannot hash clipboard data");
+    BYTE digest[32]{}; DWORD size = sizeof(digest);
+    if (!CryptGetHashParam(state.hash, HP_HASHVAL, digest, &size, 0) || size != sizeof(digest))
+        throw std::runtime_error("Cannot read clipboard hash");
+    static constexpr char hex[] = "0123456789abcdef";
+    std::string result; result.reserve(64);
+    for (auto b : digest) { result += hex[b >> 4]; result += hex[b & 15]; }
+    return result;
+}
+static void imageFingerprints(Entry &entry, const Clip &clip, bool decodePixels = true)
+{
+    const auto *image = clipboardImageFormat(clip);
+    if (!image) return;
+    if (entry.imageHash.empty())
+        entry.imageHash = std::to_string(image->id) + ":" + utf8(image->name) + ":" + clipboardHash(image->data);
+    if (!decodePixels) return;
+    try {
+        auto pixels = decodeImage(clip);
+        entry.pixelHash = std::to_string(pixels.width) + "x" + std::to_string(pixels.height) + ":" + clipboardHash(pixels.bgra);
+    } catch (const std::exception &) {
+        // Undecodable images can still be compared by their original bytes.
+    }
+}
+bool sameClipboardImage(const Clip &a, const Clip &b)
+{
+    const auto *left = clipboardImageFormat(a), *right = clipboardImageFormat(b);
     if (!left || !right)
         return false;
     if (left->id == right->id && left->name == right->name && left->data == right->data)
@@ -483,15 +687,40 @@ void History::add(const Clip &clip, const std::wstring &app, const Settings &s)
     auto data = encodeClip(clip);
     if (data.size() > uint64_t(s.maxImageMiB) * 1024 * 1024)
         return;
+    bool image = false, files = false;
+    for (const auto &f : clip.formats)
+    {
+        image |= f.id == CF_DIB || f.id == CF_DIBV5 || f.name == L"PNG";
+        files |= f.id == CF_HDROP;
+    }
     std::lock_guard lock(mutex_);
-    // Compare only the newest record; never keep image payloads in the resident index.
-    if (!entries_.empty())
+    Entry fingerprints;
+    fingerprints.contentHash = clipboardHash(data);
+    if (!entries_.empty() && entries_.front().contentHash == fingerprints.contentHash)
+        return;
+    imageFingerprints(fingerprints, clip, false);
+    if (!entries_.empty() && !fingerprints.imageHash.empty() && entries_.front().imageHash == fingerprints.imageHash)
+        return;
+    imageFingerprints(fingerprints, clip);
+    // Different payload kinds cannot be duplicates. Consult the index first so
+    // copying text after a screenshot never loads/decrypts the previous image.
+    if (!entries_.empty() && entries_.front().image == image && entries_.front().files == files)
     {
         try
         {
-            auto previous = load(entries_.front().id);
-            if (encodeClip(previous) == data || sameClipboardImage(previous, clip))
+            auto &previous = entries_.front();
+            bool migrated = previous.contentHash.empty();
+            if (migrated) {
+                auto oldClip = load(previous.id);
+                previous.contentHash = clipboardHash(encodeClip(oldClip));
+                imageFingerprints(previous, oldClip);
+            }
+            if (previous.contentHash == fingerprints.contentHash ||
+                (!fingerprints.imageHash.empty() && previous.imageHash == fingerprints.imageHash) ||
+                (!fingerprints.pixelHash.empty() && previous.pixelHash == fingerprints.pixelHash)) {
+                if (migrated) saveIndex();
                 return;
+            }
         }
         catch (...)
         {
@@ -506,12 +735,6 @@ void History::add(const Clip &clip, const std::wstring &app, const Settings &s)
     auto encrypted = protect(data);
     atomicWrite(folder_ / (id + L".dat"), encrypted);
     auto text = clip.text();
-    bool image = false, files = false;
-    for (auto &f : clip.formats)
-    {
-        image |= f.id == CF_DIB || f.id == CF_DIBV5 || f.name == L"PNG";
-        files |= f.id == CF_HDROP;
-    }
     if (text.empty())
         text = files ? L"[Files]" : image ? L"[Image]" : L"[Clipboard data]";
     for (auto &c : text)
@@ -524,7 +747,8 @@ void History::add(const Clip &clip, const std::wstring &app, const Settings &s)
     entries_.insert(entries_.begin(),
                     Entry{id, text, app, encrypted.size(),
                           (uint64_t(now.dwHighDateTime) << 32) | now.dwLowDateTime, false, image, files,
-                          image ? 1 : 0, ocrProfile(s)});
+                          image ? 1 : 0, ocrProfile(s), std::move(fingerprints.contentHash),
+                          std::move(fingerprints.imageHash), std::move(fingerprints.pixelHash)});
     prune(s);
     saveIndex();
 }
@@ -563,6 +787,103 @@ void History::clear()
         std::filesystem::remove(folder_ / (e.id + L".ocr"), ec);
     }
 }
+static Bytes historyImageJob(const std::filesystem::path &folder, const std::wstring &id,
+                             const Json &job, const std::function<bool()> &cancelled)
+{
+    if (!validId(id)) throw std::runtime_error("Invalid history ID");
+    if (cancelled && cancelled()) throw std::runtime_error("History OCR cancelled");
+    auto request = std::filesystem::absolute(folder) / (L"ocr-" + newSnippetId() + L".request");
+    auto response = request; response += L".result";
+    struct Cleanup {
+        std::filesystem::path request, response;
+        ~Cleanup() {
+            std::error_code ignored;
+            std::filesystem::remove(request, ignored);
+            std::filesystem::remove(response, ignored);
+        }
+    } cleanup{request, response};
+    atomicWrite(request, protect(jsonBytes(job)));
+    auto helper = std::filesystem::path(executable()).parent_path() / L"KSwitcher.Screenshot.exe";
+    auto command = L"\"" + helper.wstring() + L"\" --history-ocr \"" + request.wstring() + L"\"";
+    STARTUPINFOW startup{sizeof(startup)};
+    startup.dwFlags = STARTF_USESHOWWINDOW; startup.wShowWindow = SW_HIDE;
+    PROCESS_INFORMATION process{};
+    if (!CreateProcessW(helper.c_str(), command.data(), nullptr, nullptr, FALSE, CREATE_NO_WINDOW,
+                        nullptr, helper.parent_path().c_str(), &startup, &process))
+        throw std::runtime_error(utf8(lastError(L"Cannot start history OCR helper")));
+    CloseHandle(process.hThread);
+    struct Child {
+        HANDLE handle;
+        ~Child() {
+            if (WaitForSingleObject(handle, 0) != WAIT_OBJECT_0) {
+                TerminateProcess(handle, ERROR_CANCELLED);
+                WaitForSingleObject(handle, INFINITE);
+            }
+            CloseHandle(handle);
+        }
+    } child{process.hProcess};
+    auto deadline = GetTickCount64() + 60000;
+    for (;;) {
+        auto wait = WaitForSingleObject(child.handle, 100);
+        if (wait == WAIT_OBJECT_0) break;
+        if (wait != WAIT_TIMEOUT) throw std::runtime_error("Cannot wait for history OCR helper");
+        if (cancelled && cancelled()) throw std::runtime_error("History OCR cancelled");
+        if (GetTickCount64() >= deadline) throw std::runtime_error("History OCR helper timed out");
+    }
+    DWORD result{};
+    if (!GetExitCodeProcess(child.handle, &result) || result)
+        throw std::runtime_error("History OCR helper failed: " + std::to_string(result));
+    return unprotect(readFile(response, 8 * 1024 * 1024));
+}
+std::wstring History::recognizeImage(const std::wstring &id, const Settings &settings,
+                                    const std::function<bool()> &cancelled) const
+{
+    Json job{{"schema", 1}, {"id", utf8(id)}, {"tesseract", settings.useTesseract},
+             {"path", utf8(settings.tesseractPath)}, {"languages", utf8(settings.tesseractLanguages)}};
+    auto reply = parse(historyImageJob(folder_, id, job, cancelled));
+    if (reply.at("schema") != 1 || str(reply, "id") != id)
+        throw std::runtime_error("Invalid history OCR response");
+    return str(reply, "text");
+}
+Pixels History::thumbnail(const std::wstring &id, const std::function<bool()> &cancelled) const
+{
+    auto bytes = historyImageJob(folder_, id, Json{{"schema", 1}, {"id", utf8(id)}, {"thumbnail", true}}, cancelled);
+    size_t at = 0;
+    auto width = get32(bytes, at), height = get32(bytes, at);
+    if (!width || !height || width > 208 || height > 128 || bytes.size() - at != width * height * 4)
+        throw std::runtime_error("Invalid history thumbnail response");
+    bytes.erase(bytes.begin(), bytes.begin() + at);
+    return Pixels{width, height, std::move(bytes)};
+}
+int runHistoryOcr(const std::filesystem::path &request)
+{
+    try {
+        if (!request.is_absolute() || !request.filename().wstring().starts_with(L"ocr-") ||
+            request.extension() != L".request") return 1;
+        auto job = parse(unprotect(readFile(request, 1024 * 1024)));
+        auto id = str(job, "id");
+        if (job.at("schema") != 1 || !validId(id)) return 1;
+        auto clip = decodeClip(unprotect(readFile(request.parent_path() / (id + L".dat"), 80 * 1024 * 1024)));
+        if (job.value("thumbnail", false)) {
+            auto pixels = decodeImage(clip, 208, 128);
+            if (!pixels.width || !pixels.height) return 1;
+            Bytes reply;
+            put32(reply, pixels.width); put32(reply, pixels.height);
+            reply.insert(reply.end(), pixels.bgra.begin(), pixels.bgra.end());
+            atomicWrite(request.wstring() + L".result", protect(reply));
+            return 0;
+        }
+        Settings settings;
+        settings.useTesseract = job.at("tesseract").get<bool>();
+        settings.tesseractPath = str(job, "path");
+        settings.tesseractLanguages = str(job, "languages");
+        auto text = utf8(recognizeText(clip, settings));
+        if (text.size() > 1024 * 1024) return 1;
+        auto response = request; response += L".result";
+        atomicWrite(response, protect(jsonBytes(Json{{"schema", 1}, {"id", utf8(id)}, {"text", text}})));
+        return 0;
+    } catch (...) { return 1; }
+}
 bool History::saveOcr(const std::wstring &id, const std::optional<std::wstring> &text, const Settings &settings)
 {
     std::lock_guard lock(mutex_);
@@ -603,9 +924,10 @@ std::optional<std::wstring> History::ocrText(const std::wstring &id, const std::
     if (bytes.empty() || bytes.front() != 1) throw std::runtime_error("Invalid OCR text format");
     return wide(std::string(bytes.begin() + 1, bytes.end()));
 }
-std::vector<Entry> History::search(const std::wstring &query) const
+std::vector<Entry> History::search(const std::wstring &query, bool pinnedOnly) const
 {
     auto items = entries();
+    if (pinnedOnly) std::erase_if(items, [](const Entry &entry) { return !entry.pinned; });
     if (query.empty())
         return items;
     auto q = lower(query);

src/storage.h

@@ -1,8 +1,10 @@
 #pragma once
 #include "platform.h"
 #include <mutex>
+#include <functional>
 namespace ks
 {
+struct Pixels;
 Settings loadSettings(const std::filesystem::path &, const std::vector<Layout> &);
 Settings decodeSettings(const Bytes &, const std::vector<Layout> &);
 Bytes encodeSettings(const Settings &);
@@ -15,6 +17,7 @@ struct Entry
     bool pinned{}, image{}, files{};
     int ocrState{}; // 0: legacy/not applicable, 1: pending, 2: saved, 3: failed
     std::wstring ocrProfile = L"windows";
+    std::string contentHash, imageHash, pixelHash;
 };
 class History
 {
@@ -22,21 +25,45 @@ class History
     std::vector<Entry> entries_;
     mutable std::mutex mutex_;
     void saveIndex();
+    void loadIndex();
     void prune(const Settings &);
 
   public:
     explicit History(const std::filesystem::path &);
+    void reload();
     std::vector<Entry> entries() const;
     Clip load(const std::wstring &id) const;
     void add(const Clip &, const std::wstring &app, const Settings &);
+    bool captureImage(DWORD sequence, const std::wstring &app, const Settings &);
+    std::wstring recognizeImage(const std::wstring &id, const Settings &,
+                                const std::function<bool()> &cancelled = {}) const;
+    Pixels thumbnail(const std::wstring &id, const std::function<bool()> &cancelled = {}) const;
     bool saveOcr(const std::wstring &id, const std::optional<std::wstring> &, const Settings &);
     std::optional<std::wstring> ocrText(const std::wstring &id, const std::wstring &profile = L"") const;
     void remove(const std::wstring &);
     void pin(const std::wstring &);
     void clear();
-    std::vector<Entry> search(const std::wstring &) const;
+    std::vector<Entry> search(const std::wstring &, bool pinnedOnly = false) const;
 };
 Bytes encodeClip(const Clip &);
 Clip decodeClip(const Bytes &);
 bool sameClipboardImage(const Clip &, const Clip &);
+int runImageHistoryCapture(const std::filesystem::path &request);
+int runHistoryOcr(const std::filesystem::path &request);
+// Image backups stay encrypted on disk and are read/written only by a short-lived helper.
+class ClipboardSnapshot
+{
+    Clip clip_;
+    std::filesystem::path request_;
+    void cleanup() noexcept;
+    DWORD run(bool restore, DWORD sequence);
+  public:
+    ClipboardSnapshot() = default;
+    ClipboardSnapshot(const ClipboardSnapshot &) = delete;
+    ClipboardSnapshot &operator=(const ClipboardSnapshot &) = delete;
+    ~ClipboardSnapshot();
+    void capture(HWND, DWORD sequence);
+    DWORD restore(HWND, DWORD sequence);
+};
+int runClipboardSnapshot(const std::filesystem::path &request);
 } // namespace ks

src/ui.cpp

@@ -83,7 +83,7 @@ void arrangeWindow(HWND w)
     {
         int id = GetDlgCtrlID(child);
         RECT next{scale(w, r.left) - layout->x,
-                  scale(w, r.top) - layout->y + (id >= 110 && id <= 114 ? extraHeight : 0)};
+                  scale(w, r.top) - layout->y + ((id >= 110 && id <= 114) || id == 116 ? extraHeight : 0)};
         next.right = next.left + scale(w, r.right - r.left) + (id == 101 || id == 102 ? extraWidth : 0);
         next.bottom = next.top + scale(w, r.bottom - r.top) + (id == 102 ? extraHeight : 0);
         if (child == layout->stretch)
@@ -468,23 +468,31 @@ struct SearchResult
     uint64_t generation;
     std::vector<Entry> items;
 };
+struct TextPreview
+{
+    std::string rtf;
+    std::wstring plain;
+};
 struct PreviewResult
 {
     uint64_t generation;
     std::wstring id;
     Pixels pixels;
-    std::string rtf;
+    TextPreview text;
 };
 struct HistoryView
 {
     App *app{};
     std::vector<Entry> items;
+    std::wstring rememberedSelection, rememberedTop;
     uint64_t generation{};
+    std::shared_ptr<std::atomic<bool>> previewActive = std::make_shared<std::atomic<bool>>(true);
     std::map<std::wstring, Pixels> thumbnails;
-    std::map<std::wstring, std::string> richTexts;
+    std::map<std::wstring, TextPreview> richTexts;
     HWND rich{};
     std::set<std::wstring> pending;
     bool scrolling{};
+    bool closed{};
 };
 bool selectedImage(HWND w, HistoryView *v)
 {
@@ -502,16 +510,20 @@ std::wstring selected(HWND w, HistoryView *v)
 }
 void search(HWND w, HistoryView *v)
 {
+    v->previewActive->store(false);
+    v->previewActive = std::make_shared<std::atomic<bool>>(true);
+    v->closed = false;
     auto q = value(w, 101);
+    const bool pinnedOnly = SendDlgItemMessageW(w, 117, BM_GETCHECK, 0, 0) == BST_CHECKED;
     auto generation = ++v->generation;
     v->pending.clear();
     auto *app = v->app;
     app->enqueueHistorySearch(
-        [w, app, q, generation]
+        [w, app, q, generation, pinnedOnly]
         {
             try
             {
-                auto result = new SearchResult{generation, app->history->search(q)};
+                auto result = new SearchResult{generation, app->history->search(q, pinnedOnly)};
                 if (!PostMessageW(w, ResultsMessage, 0, (LPARAM)result))
                     delete result;
             }
@@ -529,23 +541,31 @@ void requestPreview(HWND w, HistoryView *v, const Entry &entry)
     if (v->thumbnails.contains(id) || v->richTexts.contains(id) || !v->pending.insert(id).second)
         return;
     auto generation = v->generation;
+    auto active = v->previewActive;
     auto *app = v->app;
     app->enqueue(
-        [w, app, id, generation, image]
+        [w, app, id, generation, image, active]
         {
+            if (!active->load()) return;
             auto result = new PreviewResult{generation, id, {}, {}};
             try
             {
-                auto clip = app->history->load(id);
                 if (image)
-                    result->pixels = decodeImage(clip, 208, 128);
-                else
-                    result->rtf = richPreview(clip);
+                    result->pixels = app->history->thumbnail(id, [active] { return !active->load(); });
+                else {
+                    auto clip = app->history->load(id);
+                    if (!active->load()) { delete result; return; }
+                    result->text.rtf = richPreview(clip, false);
+                    if (result->text.rtf.empty()) {
+                        result->text.plain = clip.text();
+                        if (result->text.plain.size() > 4096) result->text.plain.resize(4096);
+                    }
+                }
             }
             catch (const std::exception &)
             {
             }
-            if (!PostMessageW(w, PreviewMessage, 0, (LPARAM)result))
+            if (!active->load() || !PostMessageW(w, PreviewMessage, 0, (LPARAM)result))
                 delete result;
         });
 }
@@ -599,9 +619,13 @@ void drawHistoryRow(HWND w, HistoryView *v, const DRAWITEMSTRUCT &draw)
     if (!entry.image && !entry.files)
     {
         auto rich = v->richTexts.find(entry.id);
-        if (rich != v->richTexts.end() && v->rich && !rich->second.empty())
+        if (rich != v->richTexts.end() && rich->second.rtf.empty())
+            text = (entry.pinned ? L"★  " : L"") + rich->second.plain;
+        if (rich != v->richTexts.end() && !rich->second.rtf.empty() && !v->rich)
+            v->rich = createRichText(w, 105, false);
+        if (rich != v->richTexts.end() && v->rich && !rich->second.rtf.empty())
         {
-            setRichText(v->rich, rich->second);
+            setRichText(v->rich, rich->second.rtf);
             CHARFORMAT2W format{};
             format.cbSize = sizeof(format);
             format.dwMask = CFM_COLOR;
@@ -716,6 +740,12 @@ LRESULT CALLBACK historyProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
         case WM_COMMAND:
         {
             int id = LOWORD(wp);
+            if (id == 117 && HIWORD(wp) == BN_CLICKED)
+            {
+                KillTimer(w, 1);
+                search(w, v);
+                return 0;
+            }
             if (id == 101 && HIWORD(wp) == EN_CHANGE)
             {
                 // Reject an older result even during the debounce interval.
@@ -730,6 +760,13 @@ LRESULT CALLBACK historyProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             }
             if (id == 102 && HIWORD(wp) == LBN_DBLCLK)
                 id = 110;
+            if (id == 116)
+            {
+                if (MessageBoxW(w, L"Delete all clipboard history, including pinned items? This also deletes items hidden by the current search.",
+                                L"Clear history", MB_YESNO | MB_ICONWARNING | MB_DEFBUTTON2) == IDYES)
+                    v->app->clearHistory();
+                return 0;
+            }
             auto entry = selected(w, v);
             if (id == 110 || id == 111)
             {
@@ -741,7 +778,10 @@ LRESULT CALLBACK historyProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             {
                 if (!entry.empty())
                 {
-                    if (id == 112)
+                    if (v->app->historyService) {
+                        v->app->remoteHistory(id == 112 ? "pin" : "remove", entry);
+                        v->app->history->reload();
+                    } else if (id == 112)
                         v->app->history->pin(entry);
                     else
                         v->app->history->remove(entry);
@@ -763,6 +803,7 @@ LRESULT CALLBACK historyProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
         }
         case WM_TIMER:
             KillTimer(w, 1);
+            if (v->closed) return 0;
             search(w, v);
             return 0;
         case ResultsMessage:
@@ -771,8 +812,10 @@ LRESULT CALLBACK historyProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             if (result->generation != v->generation)
                 return 0;
             auto old = selected(w, v);
+            if (old.empty()) old = v->rememberedSelection;
             int top=(int)SendDlgItemMessageW(w,102,LB_GETTOPINDEX,0,0);
             auto topId=top>=0 && top<(int)v->items.size()?v->items[top].id:L"";
+            if (topId.empty()) topId = v->rememberedTop;
             v->items = std::move(result->items);
             SendDlgItemMessageW(w, 102, WM_SETREDRAW, FALSE, 0);
             SendDlgItemMessageW(w, 102, LB_RESETCONTENT, 0, 0);
@@ -812,12 +855,14 @@ LRESULT CALLBACK historyProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
                 visible.insert(v->items[i].id);
                 if(v->items[i].id==result->id) { changed=intersection; repaint=true; }
             }
-            if (!result->rtf.empty())
-                v->richTexts[result->id] = std::move(result->rtf);
+            if (!result->text.rtf.empty() || !result->text.plain.empty())
+                v->richTexts[result->id] = std::move(result->text);
             else
                 v->thumbnails[result->id] = std::move(result->pixels);
-            trimHistoryPreviews(v->thumbnails,visible);
-            trimHistoryPreviews(v->richTexts,visible);
+            trimHistoryPreviews(v->thumbnails,visible,32,HistoryThumbnailBudget,
+                                [](const Pixels &p) { return p.bgra.capacity(); });
+            trimHistoryPreviews(v->richTexts,visible,32,HistoryRichTextBudget,
+                                [](const TextPreview &s) { return s.rtf.capacity() + s.plain.capacity() * sizeof(wchar_t); });
             if(repaint) InvalidateRect(list,&changed,FALSE);
             return 0;
         }
@@ -860,6 +905,7 @@ LRESULT CALLBACK historyProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             AppendMenuW(menu, MF_STRING, 113, L"&Delete");
             AppendMenuW(menu, MF_STRING, 114, selectedImage(w,v)?L"&Edit image in screenshot editor":L"&Open full item");
             AppendMenuW(menu, MF_STRING, 115, L"&Copy text from image (OCR)");
+            showMenuAccessKeys(menu);
             int cmd = TrackPopupMenu(menu, TPM_RETURNCMD, p.x, p.y, 0, w, nullptr);
             DestroyMenu(menu);
             if (cmd)
@@ -867,15 +913,29 @@ LRESULT CALLBACK historyProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             return 0;
         }
         case WM_CLOSE:
+        {
+            v->rememberedSelection = selected(w, v);
+            int top = (int)SendDlgItemMessageW(w,102,LB_GETTOPINDEX,0,0);
+            v->rememberedTop = top >= 0 && top < (int)v->items.size() ? v->items[top].id : L"";
+            v->app->saveHistoryView(v->rememberedSelection, v->rememberedTop, value(w, 101),
+                                   SendDlgItemMessageW(w, 117, BM_GETCHECK, 0, 0) == BST_CHECKED);
+            KillTimer(w, 1);
+            v->closed = true;
+            v->previewActive->store(false);
+            ++v->generation; // Discard search/preview results queued before closing.
             ShowWindow(w, SW_HIDE);
+            SendDlgItemMessageW(w,102,LB_RESETCONTENT,0,0);
+            std::vector<Entry>().swap(v->items);
             v->thumbnails.clear();
             v->richTexts.clear();
-            if (v->rich)
-                SetWindowTextW(v->rich, L"");
+            if (v->rich) SetWindowTextW(v->rich, L"");
             v->pending.clear();
-            ++v->generation;
+            if (v->app->historyService && !v->app->historyEntryWindows)
+                PostMessageW(v->app->window, WM_CLOSE, 0, 0);
             return 0;
+        }
         case WM_NCDESTROY:
+            v->previewActive->store(false);
             disposeFont(w);
             v->app->historyWindow = nullptr;
             delete v;
@@ -1331,6 +1391,46 @@ void showOcrOptions(HWND parent, SettingsView *v)
     showRequestedWindow(w); SetForegroundWindow(w);
 }
 #include "ui_sync.inl"
+bool settingsChanged(HWND w, SettingsView *v)
+{
+    try
+    {
+        return encodeSettings(collectSettings(w, v)) != encodeSettings(v->app->settings);
+    }
+    catch (const std::exception &)
+    {
+        // Invalid edits are unsaved changes too. Allow discarding them without
+        // requiring the user to repair the fields first.
+        return true;
+    }
+}
+void closeSettings(HWND w, SettingsView *v)
+{
+    if (settingsChanged(w, v))
+    {
+        int choice = MessageBoxW(w,
+            L"You have unsaved settings changes. Save them before closing?\n\n"
+            L"Yes: save and close.\nNo: discard changes.\nCancel: keep editing.",
+            L"KSwitcher — Unsaved settings", MB_YESNOCANCEL | MB_ICONWARNING | MB_DEFBUTTON3);
+        if (choice != IDYES && choice != IDNO)
+            return;
+        if (choice == IDYES)
+        {
+            try
+            {
+                if (v->app->busy)
+                    throw std::runtime_error("Wait for the current text operation to finish");
+                v->app->applySettings(collectSettings(w, v));
+            }
+            catch (const std::exception &e)
+            {
+                error(w, e);
+                return;
+            }
+        }
+    }
+    DestroyWindow(w);
+}
 LRESULT CALLBACK settingsProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
 {
     if (msg == WM_DPICHANGED)
@@ -1396,7 +1496,7 @@ LRESULT CALLBACK settingsProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             }
             if (id == IDCANCEL)
             {
-                DestroyWindow(w);
+                closeSettings(w, v);
                 return 0;
             }
             if (id == 250)
@@ -1447,7 +1547,7 @@ LRESULT CALLBACK settingsProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             break;
         }
         case WM_CLOSE:
-            DestroyWindow(w);
+            closeSettings(w, v);
             return 0;
         case WM_NCDESTROY:
             disposeFont(w);
@@ -1595,13 +1695,19 @@ LRESULT CALLBACK snippetProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
 #ifndef KS_CONFIG_APP
 LRESULT CALLBACK entryProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
 {
+    if (msg == WM_NCCREATE)
+        SetWindowLongPtrW(w, GWLP_USERDATA, (LONG_PTR)((CREATESTRUCTW *)lp)->lpCreateParams);
     if (msg == WM_SIZE)
     {
         MoveWindow(GetDlgItem(w, 1), 10, 10, LOWORD(lp) - 20, HIWORD(lp) - 20, TRUE);
         return 0;
     }
-    if (msg == WM_NCDESTROY)
+    if (msg == WM_NCDESTROY) {
         disposeFont(w);
+        auto *app = (App *)GetWindowLongPtrW(w, GWLP_USERDATA);
+        if (app && app->historyService && app->historyEntryWindows && !--app->historyEntryWindows &&
+            !IsWindowVisible(app->historyWindow)) PostMessageW(app->window, WM_CLOSE, 0, 0);
+    }
     return DefWindowProcW(w, msg, wp, lp);
 }
 #endif
@@ -1609,6 +1715,7 @@ LRESULT CALLBACK entryProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
 #ifndef KS_CONFIG_APP
 void refreshHistory(App &app)
 {
+    if (app.isolateHistory) { app.refreshHistoryProcess(); return; }
     if (app.historyWindow)
     {
         auto *v = (HistoryView *)GetWindowLongPtrW(app.historyWindow, GWLP_USERDATA);
@@ -1617,6 +1724,7 @@ void refreshHistory(App &app)
 }
 void showHistory(App &app, bool visible)
 {
+    if (app.isolateHistory) { if (visible) app.openHistoryProcess(); return; }
     if (!app.history)
     {
         app.report(L"Clipboard history is unavailable. See the log in the data folder.");
@@ -1637,9 +1745,11 @@ void showHistory(App &app, bool visible)
         HWND w = makeWindow(app, L"KSwitcher.History", L"Clipboard history", historyProc, 760, 500);
         app.historyWindow = w;
         windowLayoutState(w)->history = true;
-        ((HistoryView *)GetWindowLongPtrW(w, GWLP_USERDATA))->rich = createRichText(w, 105, false);
-        label(w, L"&Search clipboard history", 16, 12, 500);
-        edit(w, 101, 16, 38, 728);
+        auto filter = control(w, L"BUTTON", L"★ Pinned only", WS_TABSTOP | BS_AUTOCHECKBOX,
+                              117, 16, 38, 112, 25);
+        SendMessageW(filter, BM_SETCHECK, app.historyPinnedOnly ? BST_CHECKED : BST_UNCHECKED, 0);
+        label(w, L"&Search clipboard history", 136, 12, 500);
+        edit(w, 101, 136, 38, 608);
         auto list = control(w, L"LISTBOX", L"",
                             WS_TABSTOP | WS_VSCROLL | LBS_NOTIFY | LBS_NOINTEGRALHEIGHT | WS_BORDER |
                                 LBS_OWNERDRAWFIXED | LBS_HASSTRINGS,
@@ -1650,8 +1760,15 @@ void showHistory(App &app, bool visible)
         button(w, L"P&in / unpin", 112, 222, 452, 110);
         button(w, L"&Delete", 113, 340, 452, 90);
         button(w, L"&Open item", 114, 438, 452, 100);
+        button(w, L"Clear &history…", 116, 546, 452, 150);
         SetWindowSubclass(list, historyKey, 1, (DWORD_PTR)w);
         SetWindowSubclass(GetDlgItem(w, 101), historyKey, 1, (DWORD_PTR)w);
+        if (app.historyService) {
+            auto *v = (HistoryView *)GetWindowLongPtrW(w, GWLP_USERDATA);
+            v->rememberedSelection = app.historySelection;
+            v->rememberedTop = app.historyTop;
+            SetDlgItemTextW(w, 101, app.historyQuery.c_str());
+        }
     }
     if (!visible) return;
     POINT cursor;
@@ -1808,6 +1925,7 @@ void showEntry(App &app, const std::wstring &id)
         }
         HWND w = makeWindow(app, L"KSwitcher.Entry", L"Clipboard item", entryProc, 720, 500,
                             WS_THICKFRAME | WS_MAXIMIZEBOX);
+        if (app.historyService) ++app.historyEntryWindows;
         auto field = edit(w, 1, 10, 10, 700, 480, ES_MULTILINE | ES_READONLY | ES_AUTOVSCROLL | WS_VSCROLL);
         SetWindowTextW(field, text.c_str());
         showRequestedWindow(w);

src/update.h

@@ -2,7 +2,7 @@
 #include "platform.h"
 namespace ks
 {
-inline constexpr wchar_t AppVersion[] = L"0.6.28";
+inline constexpr wchar_t AppVersion[] = L"0.6.42";
 inline constexpr UINT UpdateMessage = WM_APP + 7;
 inline constexpr UINT UpdateCheckIntervalMs = 6 * 60 * 60 * 1000;
 inline constexpr UINT UpdateNotificationRetryMs = 5 * 60 * 1000;

tests/clipboard_snapshot.cpp

@@ -0,0 +1,108 @@
+// Run with the resident stopped. The suite restores the original clipboard.
+#include "storage.h"
+#include "ocr.h"
+#include <psapi.h>
+#include <iostream>
+#include <algorithm>
+static void require(bool ok, const char *name) {
+    if (!ok) throw std::runtime_error(name);
+    std::cout << "PASS " << name << '\n';
+}
+static HWND owner() {
+    return CreateWindowExW(0,L"STATIC",L"Snapshot test",0,0,0,0,0,HWND_MESSAGE,nullptr,nullptr,nullptr);
+}
+static void child(const std::wstring &argument) {
+    auto exe=ks::executable(), command=L"\""+exe+L"\" "+argument;
+    STARTUPINFOW startup{sizeof(startup)}; startup.dwFlags=STARTF_USESHOWWINDOW; startup.wShowWindow=SW_HIDE;
+    PROCESS_INFORMATION p{};
+    if(!CreateProcessW(exe.c_str(),command.data(),nullptr,nullptr,FALSE,CREATE_NO_WINDOW,nullptr,nullptr,&startup,&p))
+        throw std::runtime_error("start fixture process");
+    CloseHandle(p.hThread);
+    auto wait=WaitForSingleObject(p.hProcess,30000); DWORD code=1;
+    if(wait!=WAIT_OBJECT_0) {TerminateProcess(p.hProcess,1);WaitForSingleObject(p.hProcess,INFINITE);}
+    GetExitCodeProcess(p.hProcess,&code); CloseHandle(p.hProcess);
+    if(code) throw std::runtime_error("fixture process failed");
+}
+static size_t resident() {
+    ks::Bytes b(1024*1024); auto ws=reinterpret_cast<PSAPI_WORKING_SET_INFORMATION*>(b.data());
+    if(!QueryWorkingSet(GetCurrentProcess(),ws,DWORD(b.size()))) throw std::runtime_error("working set query");
+    size_t pages=0; for(size_t i=0;i<ws->NumberOfEntries;++i) if(!ws->WorkingSetInfo[i].Shared) ++pages;
+    return pages*4096;
+}
+static void verifyImage(HWND w) {
+    auto c=ks::readClipboard(w,64*1024*1024);
+    for(auto id:{CF_DIB,CF_DIBV5}) {
+        auto it=std::find_if(c.formats.begin(),c.formats.end(),[&](const auto &f){return f.id==UINT(id);});
+        require(it!=c.formats.end(),"restores image representation");
+        auto pixels=ks::decodeImage(ks::Clip{{*it}});
+        require(pixels.width==1566 && pixels.height==1068 && pixels.bgra.front()==77,"preserves image pixels");
+    }
+    require(c.text()==L"Snapshot mixed text","preserves accompanying text");
+}
+int main(int argc,char**argv) {
+    CoInitializeEx(nullptr,COINIT_MULTITHREADED);
+    HWND w=owner(); int result=0; ks::Clip original; bool saved=false;
+    try {
+        std::string mode=argc>1?argv[1]:"suite";
+        if(mode=="publish") {
+            ks::Pixels p{1566,1068,ks::Bytes(1566*1068*4,255)}; p.bgra[0]=77;
+            auto dib=ks::imageDib(p); auto v5=dib;
+            BITMAPV5HEADER h{}; h.bV5Size=sizeof(h); h.bV5Width=p.width; h.bV5Height=-p.height;
+            h.bV5Planes=1; h.bV5BitCount=32; h.bV5Compression=BI_BITFIELDS;
+            h.bV5RedMask=0xff0000; h.bV5GreenMask=0xff00; h.bV5BlueMask=0xff; h.bV5AlphaMask=0xff000000;
+            v5.id=CF_DIBV5; v5.data.resize(sizeof(h)+p.bgra.size());
+            memcpy(v5.data.data(),&h,sizeof(h)); memcpy(v5.data.data()+sizeof(h),p.bgra.data(),p.bgra.size());
+            auto clip=ks::textClip(L"Snapshot mixed text"); clip.formats.push_back(dib); clip.formats.push_back(v5);
+            ks::writeClipboard(w,clip);
+        } else if(mode=="old" || mode=="new") {
+            child(L"publish"); auto baseline=resident();
+            if(mode=="old") {
+                auto clip=ks::readClipboard(w,64*1024*1024);
+                ks::writeClipboard(w,ks::textClip(L"temporary")); ks::writeClipboard(w,clip);
+            } else {
+                ks::ClipboardSnapshot snapshot; snapshot.capture(w,GetClipboardSequenceNumber());
+                auto seq=ks::writeClipboard(w,ks::textClip(L"temporary"));
+                require(snapshot.restore(w,seq)==GetClipboardSequenceNumber(),"helper returns current sequence");
+            }
+            auto after=resident();
+            auto report="baseline="+std::to_string(baseline)+" after="+std::to_string(after)+" delta="+std::to_string(int64_t(after)-int64_t(baseline))+"\n";
+            auto path=std::filesystem::path(ks::executable()).parent_path()/(L"snapshot-memory-"+ks::wide(mode)+L".txt");
+            ks::atomicWrite(path,ks::Bytes(report.begin(),report.end()));
+            verifyImage(w); // Only after measuring: verification intentionally reads images.
+        } else {
+            original=ks::readClipboard(w,128*1024*1024); saved=true;
+            child(L"old"); child(L"new"); child(L"publish");
+            auto seq=GetClipboardSequenceNumber();
+            auto selected=ks::readClipboard(w,32*1024*1024,ks::ClipboardRead::Selection);
+            require(selected.formats.size()==1 && selected.text()==L"Snapshot mixed text","selection read excludes image data");
+            bool rejected=false;
+            try {ks::readClipboard(w,32*1024*1024,ks::ClipboardRead::WithoutImages,seq);} catch(...) {rejected=true;}
+            require(rejected,"resident rejects images before reading their data");
+            {
+                ks::ClipboardSnapshot snapshot; snapshot.capture(w,seq);
+                auto stale=ks::writeClipboard(w,ks::textClip(L"temporary"));
+                ks::writeClipboard(w,ks::textClip(L"external copy")); rejected=false;
+                try {snapshot.restore(w,stale);} catch(...) {rejected=true;}
+                require(rejected && ks::readClipboard(w).text()==L"external copy","stale image restore preserves external copy");
+            }
+            {
+                ks::ClipboardSnapshot snapshot; snapshot.capture(w,GetClipboardSequenceNumber());
+                auto temporary=ks::writeClipboard(w,ks::textClip(L"temporary"));
+                snapshot.restore(w,temporary);
+                require(ks::readClipboard(w).text()==L"external copy","text snapshot fast path restores clipboard");
+            }
+            {
+                ks::Clip empty; auto seqEmpty=ks::writeClipboard(w,empty);
+                ks::ClipboardSnapshot snapshot; snapshot.capture(w,seqEmpty);
+                snapshot.restore(w,ks::writeClipboard(w,ks::textClip(L"temporary")));
+                require(ks::readClipboard(w).formats.empty(),"empty clipboard restored");
+            }
+            auto marked=ks::textClip(L"line"); marked.formats.push_back({0,L"MSDEVLineSelect",ks::Bytes{1}});
+            ks::writeClipboard(w,marked);
+            require(ks::readClipboard(w,1024,ks::ClipboardRead::Selection).formats.size()==2,"selection reader preserves editor guard metadata");
+            std::cout<<"PASS clipboard snapshot suite\n";
+        }
+    } catch(const std::exception &e) {std::cerr<<"FAIL "<<e.what()<<'\n';result=1;}
+    if(saved) try {ks::writeClipboard(w,original);} catch(...) {result=1;}
+    DestroyWindow(w); CoUninitialize(); return result;
+}

tests/dictionary.cpp

@@ -0,0 +1,85 @@
+#include "autocorrect.h"
+#include <algorithm>
+#include <chrono>
+#include <fstream>
+#include <iostream>
+#include <psapi.h>
+#include <random>
+namespace ks {
+struct AutoCorrectorRegressionAccess {
+ static int rank(const AutoCorrector &c,const std::wstring &lang,const std::wstring &word) {
+  return c.dictionaries.at(lang)->rank(word);
+ }
+ static std::vector<int> ranks(const std::filesystem::path &path,const std::vector<std::wstring> &words) {
+  AutoCorrector::Dictionary d(path);
+  std::vector<int> values;for(const auto &word:words)values.push_back(d.rank(word));return values;
+ }
+};
+}
+int main(int argc,char **argv) {
+ try {
+  auto start=std::chrono::steady_clock::now();
+  ks::AutoCorrector c;c.configure(L"dictionaries",{L"en",L"uk",L"ru"});
+  PROCESS_MEMORY_COUNTERS_EX m{};
+  GetProcessMemoryInfo(GetCurrentProcess(),reinterpret_cast<PROCESS_MEMORY_COUNTERS*>(&m),sizeof(m));
+  std::cout<<"dictionary_bytes="<<c.memoryBytes()<<" private_bytes="<<m.PrivateUsage
+   <<" load_ms="<<std::chrono::duration<double,std::milli>(std::chrono::steady_clock::now()-start).count()<<'\n';
+  struct Query {std::wstring language,word; int rank;};
+  std::vector<Query> queries;
+  for(const auto *lang:{L"en",L"uk",L"ru"}) {
+   std::ifstream input(std::filesystem::path(L"dictionaries")/(std::wstring(lang)+L".txt"));
+   std::map<std::wstring,int> expected;
+   for(std::string line;std::getline(input,line);) {
+    auto tab=line.find('\t');auto word=ks::wide(line.substr(0,tab));auto rank=std::stoi(line.substr(tab+1));
+    auto [it,added]=expected.emplace(word,rank);if(!added)it->second=std::min(it->second,rank);
+   }
+   if(expected.empty())throw std::runtime_error("Missing benchmark dictionary");
+   for(auto &[word,rank]:expected) {
+    if(ks::AutoCorrectorRegressionAccess::rank(c,lang,word)!=rank)throw std::runtime_error("Dictionary rank differs from source");
+    if(ks::AutoCorrectorRegressionAccess::rank(c,lang,word+L"~")!=0)throw std::runtime_error("False dictionary hit");
+    queries.push_back({lang,word,rank});queries.push_back({lang,word+L"~",0});
+   }
+  }
+  std::mt19937 random(42);std::shuffle(queries.begin(),queries.end(),random);
+  uint64_t checksum=0,expected=0;
+  for(auto &q:queries)expected+=q.rank;
+  start=std::chrono::steady_clock::now();
+  for(int pass=0;pass<5;++pass)for(auto &q:queries)checksum+=ks::AutoCorrectorRegressionAccess::rank(c,q.language,q.word);
+  auto ms=std::chrono::duration<double,std::milli>(std::chrono::steady_clock::now()-start).count();
+  if(checksum!=expected*5)throw std::runtime_error("Lookup checksum mismatch");
+  std::cout<<"verified_words="<<queries.size()/2<<" queries="<<queries.size()*5<<" lookup_ms="<<ms
+   <<" ns_per_lookup="<<ms*1000000/(queries.size()*5)<<" checksum="<<checksum<<'\n';
+  auto fixture=std::filesystem::temp_directory_path()/(L"KSwitcher-dictionary-"+
+      std::to_wstring(GetCurrentProcessId())+L"-"+std::to_wstring(GetTickCount64())+L".txt");
+  struct RemoveFixture { std::filesystem::path path; ~RemoveFixture(){std::error_code ec;std::filesystem::remove(path,ec);} } cleanup{fixture};
+  auto put=[&](const std::string &text){ks::atomicWrite(fixture,ks::Bytes(text.begin(),text.end()));};
+  std::string text="duplicate\t9\r\nduplicate\t2\n";
+  std::vector<std::wstring> words;
+  std::vector<int> expectedRanks;
+  for(int i=129;i>=0;--i) {
+   auto word=L"prefix_"+std::to_wstring(i);
+   text+=ks::utf8(word)+"\t"+std::to_string(i+1)+"\n";
+   words.push_back(word);expectedRanks.push_back(i+1);
+  }
+  text+=std::string(160,'x')+"\t2147483647"; // Maximum length/rank, no final newline.
+  words.insert(words.end(),{std::wstring(160,L'x'),L"DUPLICATE",L"",L"prefix_",L"zzzz"});
+  expectedRanks.insert(expectedRanks.end(),{2147483647,2,0,0,0});
+  for(auto rank:{65534,65535,65536}) {
+   auto word=std::wstring(159,L'x')+wchar_t(L'y'+rank-65534);
+   text+="\n"+ks::utf8(word)+"\t"+std::to_string(rank);
+   words.push_back(word);expectedRanks.push_back(rank);
+  }
+  put(text);
+  if(ks::AutoCorrectorRegressionAccess::ranks(fixture,words)!=expectedRanks)
+   throw std::runtime_error("Block boundaries, duplicate ranks or maximum values failed");
+  for(const auto &invalid:std::vector<std::string>{"","missing-tab","x\t0","x\t-1","x\t2147483648",std::string(161,'x')+"\t1","\t1","x\t1bad"}) {
+   put(invalid);bool rejected=false;
+   try {ks::AutoCorrectorRegressionAccess::ranks(fixture,{L"x"});}catch(const std::runtime_error &){rejected=true;}
+   if(!rejected)throw std::runtime_error("Invalid dictionary was accepted");
+  }
+  const bool baseline=argc==2 && std::string(argv[1])=="--baseline";
+  if(!baseline && c.memoryBytes()>=1536*1024)throw std::runtime_error("Bundled dictionaries exceed compact memory budget");
+  std::cout<<"Passed complete dictionary equivalence and format regressions\n";
+  return 0;
+ }catch(const std::exception&e){std::cerr<<e.what()<<'\n';return 1;}
+}

tests/history_host.cpp

@@ -0,0 +1,184 @@
+// Run from an isolated fixture folder containing KSwitcher.exe and Screenshot.exe,
+// with the normal resident stopped. Never points at the installed user's data.
+#include "storage.h"
+#include "ocr.h"
+#include "json.hpp"
+#include <commctrl.h>
+#include <psapi.h>
+#include <iostream>
+static HWND editor{};
+static bool pastedImage{};
+static LRESULT CALLBACK targetProc(HWND w,UINT message,WPARAM wp,LPARAM lp) {
+    if(message==WM_SETFOCUS && editor) {SetFocus(editor);return 0;}
+    return DefWindowProcW(w,message,wp,lp);
+}
+static void require(bool ok,const char *what) {if(!ok)throw std::runtime_error(what);std::cout<<"PASS "<<what<<'\n';}
+static void pump() {MSG m;while(PeekMessageW(&m,nullptr,0,0,PM_REMOVE)){TranslateMessage(&m);DispatchMessageW(&m);}}
+template<class F> static void until(F condition,const char *what,DWORD timeout=10000) {
+    auto end=GetTickCount64()+timeout;
+    while(!condition()){if(GetTickCount64()>=end)throw std::runtime_error(what);pump();Sleep(10);}
+}
+static LRESULT send(HWND w,UINT message,WPARAM wp=0,LPARAM lp=0) {
+    DWORD_PTR result{};
+    if(!SendMessageTimeoutW(w,message,wp,lp,SMTO_ABORTIFHUNG,5000,&result))throw std::runtime_error("window request timed out");
+    return LRESULT(result);
+}
+static void command(HWND resident,int cmd) {
+    COPYDATASTRUCT data{1,sizeof(cmd),&cmd};send(resident,WM_COPYDATA,0,LPARAM(&data));
+}
+static size_t memory(HANDLE process) {
+    ks::Bytes bytes(1024*1024);auto ws=reinterpret_cast<PSAPI_WORKING_SET_INFORMATION*>(bytes.data());
+    if(!QueryWorkingSet(process,ws,DWORD(bytes.size())))throw std::runtime_error("memory query failed");
+    size_t pages=0;for(size_t i=0;i<ws->NumberOfEntries;++i)if(!ws->WorkingSetInfo[i].Shared)++pages;
+    return pages*4096;
+}
+static std::wstring editorText() {wchar_t text[256]{};GetWindowTextW(editor,text,256);return text;}
+static LRESULT CALLBACK editProc(HWND w,UINT message,WPARAM wp,LPARAM lp,UINT_PTR,DWORD_PTR) {
+    if(message==WM_PASTE && IsClipboardFormatAvailable(CF_DIB)) {pastedImage=true;return 0;}
+    return DefSubclassProc(w,message,wp,lp);
+}
+static ks::Clip excluded(ks::Clip clip) {
+    clip.formats.push_back({0,L"ExcludeClipboardContentFromMonitorProcessing",ks::Bytes{0}});return clip;
+}
+int main() {
+    CoInitializeEx(nullptr,COINIT_APARTMENTTHREADED);
+    PROCESS_INFORMATION process{};HWND resident{},target{};ks::Clip saved;bool captured=false;int result=0;
+    try {
+        auto folder=std::filesystem::path(ks::executable()).parent_path();
+        require(folder.filename().wstring().starts_with(L"history-host-fixture-"),"isolated fixture directory");
+        require(!FindWindowW(L"KSwitcher.Main",nullptr),"normal resident is stopped");
+        WNDCLASSW targetClass{};targetClass.lpfnWndProc=targetProc;targetClass.hInstance=GetModuleHandleW(nullptr);
+        targetClass.lpszClassName=L"KSwitcher.HistoryTestDestination";RegisterClassW(&targetClass);
+        target=CreateWindowExW(0,targetClass.lpszClassName,L"KSwitcher history test destination",WS_OVERLAPPEDWINDOW|WS_VISIBLE,
+                               50,50,500,250,nullptr,nullptr,nullptr,nullptr);
+        editor=CreateWindowExW(0,L"EDIT",L"",WS_CHILD|WS_VISIBLE|ES_MULTILINE,10,10,450,180,target,nullptr,nullptr,nullptr);
+        SetWindowSubclass(editor,editProc,1,0);
+        saved=ks::readClipboard(target,128*1024*1024);captured=true;
+        ks::writeClipboard(target,excluded(ks::textClip(L"fixture clipboard")));
+        auto settings=ks::loadSettings(folder/L"missing.json",ks::readLayouts());
+        settings.autoCorrect=false;settings.writeLog=true;settings.history=true;settings.maxItems=500;settings.maxMiB=100;
+        std::filesystem::create_directories(folder/L"data");
+        ks::saveSettings(folder/L"data/settings.json",settings);
+        ks::History history(folder/L"data/history");
+        history.clear(); // This executable only runs in its dedicated fixture directory.
+        ks::Pixels pixels{1566,1068,ks::Bytes(1566*1068*4,255)};
+        auto image=ks::Clip{{ks::imageDib(pixels)}};
+        history.add(image,L"test",settings);
+        auto imageId=history.entries().front().id;
+        // Seed once rather than rewriting the encrypted index 500 times. This
+        // also avoids measuring fixture creation in the resident under test.
+        auto indexPath=folder/L"data/history/index.dat";
+        auto rows=nlohmann::json::parse(ks::unprotect(ks::readFile(indexPath,1024*1024)));
+        for(int i=0;i<499;++i) {
+            auto id=ks::lower(ks::newSnippetId().substr(1,36)),text=L"History fixture "+std::to_wstring(i);
+            auto bytes=ks::protect(ks::encodeClip(ks::textClip(text)));
+            ks::atomicWrite(folder/L"data/history"/(id+L".dat"),bytes);
+            rows.insert(rows.begin(),nlohmann::json{{"id",ks::utf8(id)},{"preview",ks::utf8(text)},
+                {"app","test"},{"bytes",bytes.size()},{"at",i+1},{"pinned",false},{"image",false},{"files",false}});
+        }
+        auto encoded=rows.dump();ks::atomicWrite(indexPath,ks::protect(ks::Bytes(encoded.begin(),encoded.end())));
+        history.reload();
+        auto textId=history.entries().front().id;
+        auto exe=folder/L"KSwitcher.exe";auto line=L"\""+exe.wstring()+L"\"";
+        STARTUPINFOW startup{sizeof(startup)};startup.dwFlags=STARTF_USESHOWWINDOW;startup.wShowWindow=SW_HIDE;
+        require(CreateProcessW(exe.c_str(),line.data(),nullptr,nullptr,FALSE,CREATE_NO_WINDOW,nullptr,folder.c_str(),&startup,&process),"start isolated resident");
+        CloseHandle(process.hThread);process.hThread=nullptr;
+        until([&]{resident=FindWindowW(L"KSwitcher.Main",nullptr);return resident!=nullptr;},"resident startup");
+        auto base=memory(process.hProcess);
+        std::string forged="{\"action\":\"clear\",\"id\":\"\",\"plain\":false}";
+        COPYDATASTRUCT forgedRequest{0x4b530200,DWORD(forged.size()),forged.data()};
+        require(send(resident,WM_COPYDATA,WPARAM(target),LPARAM(&forgedRequest))==0,
+                "history rejects requests from an untrusted process");
+        auto open=[&] {
+            require(ks::activateWindow(target),"destination foreground");SetFocus(editor);command(resident,5);
+            HWND window{};
+            until([&]{window=FindWindowW(L"KSwitcher.History",nullptr);return window&&IsWindowVisible(window);},"history startup");
+            until([&]{return send(GetDlgItem(window,102),LB_GETCOUNT)>0;},"history rows");
+            DWORD pid{};GetWindowThreadProcessId(window,&pid);
+            require(pid!=process.dwProcessId,"history belongs to a separate process");
+            return window;
+        };
+        auto close=[&](HWND window) {
+            DWORD pid{};GetWindowThreadProcessId(window,&pid);HANDLE child=OpenProcess(SYNCHRONIZE,FALSE,pid);
+            PostMessageW(window,WM_KEYDOWN,VK_ESCAPE,0); // Escape also works with focus on the window itself.
+            until([&]{return WaitForSingleObject(child,0)==WAIT_OBJECT_0;},"history helper exits after Escape");
+            CloseHandle(child);
+            require(!FindWindowW(L"KSwitcher.History",nullptr),"Escape destroys history window");
+        };
+        for(int i=0;i<3;++i){auto w=open();until([&]{return send(GetDlgItem(w,102),LB_GETCOUNT)==500;},"all history rows loaded");require(true,"all history entries visible");close(w);}
+        auto idle=memory(process.hProcess);
+        std::cout<<"MEMORY resident_before="<<base<<" after_three_closes="<<idle<<'\n';
+        require(idle<base+2*1024*1024,"repeated history does not retain UI heap in resident");
+        auto w=open();send(w,WM_COMMAND,112);
+        until([&]{history.reload();return history.entries().front().pinned;},"resident pin mutation");
+        require(history.entries().front().id==textId,"pin preserves history identity");
+        auto filter=[&](HWND window,int index) {
+            auto checkbox=GetDlgItem(window,117);
+            if(send(checkbox,BM_GETCHECK)!=(index ? BST_CHECKED : BST_UNCHECKED)) send(checkbox,BM_CLICK);
+        };
+        filter(w,1);
+        until([&]{return send(GetDlgItem(w,102),LB_GETCOUNT)==1;},"pinned filter hides unpinned entries");
+        send(GetDlgItem(w,101),WM_SETTEXT,0,LPARAM(L"History fixture 497"));
+        until([&]{return send(GetDlgItem(w,102),LB_GETCOUNT)==0;},"search cannot match an unpinned item in pinned view");
+        send(GetDlgItem(w,101),WM_SETTEXT,0,LPARAM(L"History fixture 498"));
+        until([&]{return send(GetDlgItem(w,102),LB_GETCOUNT)==1;},"history search");
+        send(w,WM_COMMAND,112);
+        until([&]{return send(GetDlgItem(w,102),LB_GETCOUNT)==0;},"unpin removes the last pinned result");
+        filter(w,0);
+        until([&]{return send(GetDlgItem(w,102),LB_GETCOUNT)==1;},"all items restores the matching unpinned entry");
+        send(w,WM_COMMAND,112);
+        filter(w,1);
+        close(w);w=open();
+        require(send(GetDlgItem(w,117),BM_GETCHECK)==BST_CHECKED,"pinned checkbox survives helper restart");
+        wchar_t query[100]{};send(GetDlgItem(w,101),WM_GETTEXT,100,LPARAM(query));
+        require(std::wstring(query)==L"History fixture 498","search survives helper restart");
+        send(w,WM_COMMAND,114);
+        HWND entry{};until([&]{entry=FindWindowW(L"KSwitcher.Entry",nullptr);return entry!=nullptr;},"full item opens");
+        DWORD childPid{};GetWindowThreadProcessId(w,&childPid);HANDLE child=OpenProcess(SYNCHRONIZE,FALSE,childPid);
+        send(GetDlgItem(w,101),WM_KEYDOWN,VK_ESCAPE);
+        require(WaitForSingleObject(child,0)==WAIT_TIMEOUT && IsWindow(entry),"full item remains usable after closing history");
+        send(entry,WM_CLOSE);
+        until([&]{return WaitForSingleObject(child,0)==WAIT_OBJECT_0;},"helper exits after last full item closes");CloseHandle(child);
+        w=open();filter(w,0);send(GetDlgItem(w,101),WM_SETTEXT,0,LPARAM(L""));
+        until([&]{return send(GetDlgItem(w,102),LB_GETCOUNT)==500;},"clear search");close(w);
+        ks::writeClipboard(target,excluded(image));
+        w=open();send(w,WM_COMMAND,111);
+        until([&]{return editorText()==L"History fixture 498";},"paste plain text into native editor");
+        until([&]{return IsClipboardFormatAvailable(CF_DIB)&&!FindWindowW(L"KSwitcher.HistoryHost",nullptr);},"image clipboard restored after paste");
+        require(ks::decodeImage(ks::readClipboard(target,64*1024*1024)).width==pixels.width,"image clipboard survives history paste");
+        auto afterPaste=memory(process.hProcess);
+        std::cout<<"MEMORY after_paste_with_image_backup="<<afterPaste<<'\n';
+        require(afterPaste<base+2*1024*1024,"image clipboard backup stays outside resident");
+        ks::writeClipboard(target,excluded(ks::textClip(L"keep clipboard")));
+        w=open();send(GetDlgItem(w,101),WM_SETTEXT,0,LPARAM(L"Image"));
+        until([&]{return send(GetDlgItem(w,102),LB_GETCOUNT)==1;},"image search");
+        pastedImage=false;send(w,WM_COMMAND,110);
+        until([&]{return pastedImage;},"image paste reaches destination");
+        until([&]{return ks::readClipboard(target).text()==L"keep clipboard";},"clipboard restored after image paste");
+        std::cout<<"MEMORY after_image_paste="<<memory(process.hProcess)<<'\n';
+        require(memory(process.hProcess)<base+2*1024*1024,"image paste does not retain full bitmap in resident");
+        until([&]{return !FindWindowW(L"KSwitcher.HistoryHost",nullptr);},"image paste helper exits");
+        w=open();send(w,WM_COMMAND,113);
+        until([&]{history.reload();return history.entries().size()==499;},"resident removes selected image");
+        GetWindowThreadProcessId(w,&childPid);child=OpenProcess(SYNCHRONIZE,FALSE,childPid);
+        // Startup update checks temporarily reject exit; retry after that
+        // operation finishes instead of treating its guard as a host leak.
+        ULONGLONG nextExit{};
+        until([&]{
+            if(WaitForSingleObject(process.hProcess,0)==WAIT_OBJECT_0) return true;
+            if(GetTickCount64()>=nextExit) {
+                command(resident,99);nextExit=GetTickCount64()+500;
+            }
+            return false;
+        },"resident accepts exit after startup update check",30000);
+        until([&]{return WaitForSingleObject(child,0)==WAIT_OBJECT_0;},"resident shutdown closes history helper");
+        CloseHandle(child);resident=nullptr;
+        std::cout<<"PASS isolated history host suite\n";
+    } catch(const std::exception &e){std::cerr<<"FAIL "<<e.what()<<" editor="<<ks::utf8(editorText())<<" foreground="<<(GetForegroundWindow()==target)<<'\n';result=1;}
+    if(resident)try{command(resident,99);}catch(...){}
+    if(process.hProcess){if(WaitForSingleObject(process.hProcess,10000)!=WAIT_OBJECT_0){TerminateProcess(process.hProcess,1);WaitForSingleObject(process.hProcess,INFINITE);}CloseHandle(process.hProcess);}
+    if(captured)try{ks::writeClipboard(target,saved);}catch(...){result=1;}
+    if(target) DestroyWindow(target);
+    CoUninitialize();
+    return result;
+}

tests/image_capture.cpp

@@ -0,0 +1,84 @@
+// Interactive clipboard test. Run with the resident stopped; the original
+// clipboard is restored. The helper must be beside this test executable.
+#include "storage.h"
+#include "ocr.h"
+#include <algorithm>
+#include <iostream>
+static void require(bool ok,const char *name) {
+    if(!ok) throw std::runtime_error(name);
+    std::cout << "PASS " << name << '\n';
+}
+int main() {
+    CoInitializeEx(nullptr,COINIT_MULTITHREADED);
+    HWND owner=CreateWindowExW(0,L"STATIC",L"Capture test",0,0,0,0,0,HWND_MESSAGE,nullptr,nullptr,nullptr);
+    ks::Clip saved; bool captured=false; int result=0;
+    auto folder=std::filesystem::temp_directory_path()/(L"KSwitcher-image-capture-"+std::to_wstring(GetCurrentProcessId()));
+    try {
+        saved=ks::readClipboard(owner,128*1024*1024); captured=true;
+        ks::Settings settings; settings.history=true;
+        ks::History history(folder);
+        history.add(ks::textClip(L"keep pinned"),L"test",settings);
+        auto pinned=history.entries().front().id; history.pin(pinned);
+        ks::Pixels pixels{32,16,ks::Bytes(32*16*4,255)};
+        ks::Clip image{{ks::imageDib(pixels),{0,L"PNG",ks::encodePng(pixels)}}};
+        auto sequence=ks::writeClipboard(owner,image);
+        require(history.captureImage(sequence,L"capture test",settings),"helper captures image");
+        auto entries=history.entries();
+        require(entries.size()==2 && entries.front().image && entries.front().ocrState==1,"resident reloads metadata with pending OCR");
+        require(entries.front().contentHash.size()==64 && !entries.front().pixelHash.empty(),
+                "helper persists fingerprints and resident reloads them");
+        require(entries.back().id==pinned && entries.back().pinned,"helper preserves existing pinned entry");
+        auto restored=history.load(entries.front().id);
+        auto thumbnail=history.thumbnail(entries.front().id);
+        require(thumbnail.width==pixels.width && thumbnail.height==pixels.height && thumbnail.bgra==pixels.bgra,
+                "helper thumbnail preserves small image pixels");
+        bool thumbnailCancelled=false;
+        try {history.thumbnail(entries.front().id,[]{return true;});} catch(...) {thumbnailCancelled=true;}
+        require(thumbnailCancelled,"closed history cancels thumbnail work");
+        auto has=[&](const ks::Format &expected) {
+            return std::any_of(restored.formats.begin(),restored.formats.end(),[&](const ks::Format &actual) {
+                return (expected.name.empty()?actual.id==expected.id:actual.name==expected.name) && actual.data==expected.data;
+            });
+        };
+        require(has(image.formats[0]) && has(image.formats[1]),
+                "encrypted history preserves both image representations");
+        require(ks::readFile(folder/(entries.front().id+L".dat"),1024*1024)!=ks::encodeClip(restored),"saved image is encrypted");
+        require(GetClipboardSequenceNumber()==sequence,"capture leaves clipboard unchanged");
+        require(history.captureImage(sequence,L"capture test",settings) && history.entries().size()==2,"duplicate capture is not added");
+        ks::writeClipboard(owner,ks::textClip(L"new clipboard"));
+        require(!history.captureImage(sequence,L"stale",settings) && history.entries().size()==2,"stale request does not save another clipboard");
+        for(auto name : {L"ExcludeClipboardContentFromMonitorProcessing",L"Clipboard Viewer Ignore",L"CanIncludeInClipboardHistory"}) {
+            auto blocked=image; blocked.formats.push_back({0,name,ks::Bytes(4,0)});
+            sequence=ks::writeClipboard(owner,blocked);
+            require(!history.captureImage(sequence,L"excluded",settings) && history.entries().size()==2,"clipboard privacy flag prevents capture");
+        }
+        pixels={1024,512,ks::Bytes(1024*512*4,255)};
+        sequence=ks::writeClipboard(owner,ks::Clip{{ks::imageDib(pixels)}});
+        settings.maxImageMiB=1;
+        bool rejected=false;
+        try {history.captureImage(sequence,L"oversized",settings);} catch(const std::exception &e) {
+            rejected=std::string(e.what())=="Clipboard exceeds the configured size limit";
+        }
+        require(rejected && history.entries().size()==2,"oversized image is rejected without changing index");
+        require(GetClipboardSequenceNumber()==sequence,"rejection leaves clipboard unchanged");
+        settings.maxImageMiB=20;
+        history.add(ks::Clip{{ks::imageDib(pixels)}},L"thumbnail fixture",settings);
+        auto largeId=history.entries().front().id;
+        thumbnail=history.thumbnail(largeId);
+        require(thumbnail.width==208 && thumbnail.height==104 && thumbnail.bgra.size()==208*104*4,
+                "large image returns only bounded thumbnail pixels");
+        history.remove(largeId);
+        bool missingRejected=false;
+        try {history.thumbnail(largeId);} catch(...) {missingRejected=true;}
+        require(missingRejected,"deleted image cannot be previewed or recreated");
+        for(const auto &file:std::filesystem::directory_iterator(folder))
+            require(file.path().extension()!=L".request","encrypted capture request is cleaned up");
+    } catch(const std::exception &e) {std::cerr << "FAIL " << e.what() << '\n';result=1;}
+    if(captured) try {ks::writeClipboard(owner,saved);} catch(...) {result=1;}
+    DestroyWindow(owner); CoUninitialize();
+    // Remove only the exact PID-specific fixture under the system temp directory.
+    std::error_code ignored;
+    if(std::filesystem::weakly_canonical(folder).parent_path()==std::filesystem::weakly_canonical(std::filesystem::temp_directory_path()))
+        std::filesystem::remove_all(folder,ignored);
+    return result;
+}

tests/input.cpp

@@ -5,6 +5,19 @@
 #include <commctrl.h>
 #include <iostream>
 #include <cmath>
+static int settingsCloseChoice = IDCANCEL;
+static int settingsClosePrompts = 0;
+static void CALLBACK answerSettingsClose(HWND, UINT, UINT_PTR, DWORD)
+{
+    HWND dialog = FindWindowW(L"#32770", L"KSwitcher — Unsaved settings");
+    DWORD process{};
+    if (dialog && GetWindowThreadProcessId(dialog, &process) == GetCurrentThreadId() &&
+        process == GetCurrentProcessId())
+    {
+        ++settingsClosePrompts;
+        SendMessageW(dialog, WM_COMMAND, settingsCloseChoice, 0);
+    }
+}
 LRESULT CALLBACK countControlMoves(HWND w, UINT message, WPARAM wp, LPARAM lp, UINT_PTR, DWORD_PTR data)
 {
     if (message == WM_WINDOWPOSCHANGING) ++*reinterpret_cast<int *>(data);
@@ -12,6 +25,38 @@ LRESULT CALLBACK countControlMoves(HWND w, UINT message, WPARAM wp, LPARAM lp, U
 }
 namespace ks {
 struct InputRegressionAccess {
+    static bool idleUndo(App &a) {
+        a.last=LastTransform{}; a.last->at=100;
+        a.releaseIdleMemory(120100);
+        if (!a.last) return false;
+        a.busy=true;
+        a.releaseIdleMemory(120101);
+        if (!a.last) { a.busy=false; return false; }
+        a.busy=false;
+        a.releaseIdleMemory(120101);
+        return !a.last;
+    }
+    static bool releasedSync(const App &a) {
+        return a.syncSnapshot.capacity()==0 && a.syncResult.settings.capacity()==0 &&
+            a.syncResult.base.capacity()==0 && a.syncResult.conflicts.capacity()==0;
+    }
+    static bool completedSync(App &a, int mode) {
+        sampleConflicts(a);
+        auto conflicts=encodeSyncConflicts(a.pendingSyncConflicts);
+        a.syncConnection=loadSyncConfig(a.data);
+        a.syncSnapshot=encodeSettings(a.settings);
+        a.syncResult={mode!=1,sharedSyncSettings(a.settings),2,L"test"};
+        a.syncResult.base=a.syncResult.settings;
+        a.syncResult.conflicts=a.pendingSyncConflicts;
+        if(mode==2) a.syncResult.settings={1,2,3}; // Decode exception after joining.
+        a.syncWorker=std::thread([]{});
+        a.syncRunning=true; a.syncDone=true; a.busy=true;
+        a.pollSync();
+        bool retained=!a.syncSnapshot.empty() && a.syncRunning;
+        a.busy=false; a.pollSync();
+        return retained && releasedSync(a) && !a.syncRunning &&
+            encodeSyncConflicts(a.pendingSyncConflicts)==conflicts;
+    }
     static inline bool delivery = true;
     static inline int notifications = 0;
     static bool notify(const std::wstring &) { ++notifications; return delivery; }
@@ -31,6 +76,7 @@ struct InputRegressionAccess {
         a.syncRunning=true; a.syncDone=true;
         a.pollSync();
         return encodeSettings(a.settings)==before && !a.syncRunning &&
+            releasedSync(a) &&
             !std::filesystem::exists(a.data/L"sync-base.bin");
     }
     static bool syncBackoff(App &a) {
@@ -80,6 +126,25 @@ int main(int argc, char **argv) {
     try {
         INITCOMMONCONTROLSEX controls{sizeof(controls),ICC_STANDARD_CLASSES|ICC_LISTVIEW_CLASSES};
         InitCommonControlsEx(&controls);
+        {
+            HMENU menu = CreatePopupMenu(), child = CreatePopupMenu();
+            AppendMenuW(menu,MF_STRING | MF_CHECKED,1,L"&Settings…");
+            AppendMenuW(menu,MF_STRING,2,L"Copy\tCtrl+C");
+            AppendMenuW(child,MF_STRING,3,L"Rock && &Roll");
+            AppendMenuW(menu,MF_POPUP,(UINT_PTR)child,L"&Pause");
+            ks::showMenuAccessKeys(menu);
+            ks::showMenuAccessKeys(menu);
+            wchar_t label[128]{};
+            GetMenuStringW(menu,1,label,128,MF_BYCOMMAND);
+            require(std::wstring(label)==L"&Settings…\tS" &&
+                    (GetMenuState(menu,1,MF_BYCOMMAND)&MF_CHECKED),
+                    "visible menu mnemonic is idempotent and preserves item state");
+            GetMenuStringW(menu,2,label,128,MF_BYCOMMAND);
+            require(std::wstring(label)==L"Copy\tCtrl+C","existing menu shortcut hints are retained");
+            GetMenuStringW(child,3,label,128,MF_BYCOMMAND);
+            require(std::wstring(label)==L"Rock && &Roll\tR","submenu hints skip escaped ampersands");
+            DestroyMenu(menu);
+        }
         {
             ks::App app(GetModuleHandleW(nullptr),true,temp);
             ks::InputRegressionAccess::setup(app);
@@ -629,6 +694,49 @@ int main(int argc, char **argv) {
             fitted=ks::fitWindowRect({2000,2000,2600,2400},{-1920,0,0,1080});
             require(fitted.left==-600&&fitted.top==680&&fitted.right==0,"negative-coordinate monitor supported");
             ks::showSettings(app,false);
+            {
+                auto timer = SetTimer(nullptr, 0, 10, answerSettingsClose);
+                require(timer != 0, "settings close prompt responder");
+                SendMessageW(app.settingsWindow, WM_CLOSE, 0, 0);
+                require(!app.settingsWindow && settingsClosePrompts == 0,
+                        "unchanged settings close without prompting");
+                ks::showSettings(app,false);
+                auto settingsWindow = app.settingsWindow;
+                auto initial = SendDlgItemMessageW(settingsWindow,205,BM_GETCHECK,0,0);
+                SendDlgItemMessageW(settingsWindow,205,BM_SETCHECK,!initial,0);
+                SendMessageW(settingsWindow, WM_CLOSE, 0, 0);
+                require(IsWindow(settingsWindow) && settingsClosePrompts == 1,
+                        "cancel close preserves changed settings");
+                SendDlgItemMessageW(settingsWindow,205,BM_SETCHECK,initial,0);
+                SendMessageW(settingsWindow, WM_CLOSE, 0, 0);
+                require(!app.settingsWindow && settingsClosePrompts == 1,
+                        "reverted settings close without prompting");
+                ks::showSettings(app,false);
+                SetDlgItemTextW(app.settingsWindow,240,L"invalid");
+                settingsCloseChoice = IDNO;
+                SendMessageW(app.settingsWindow,WM_COMMAND,IDCANCEL,0);
+                require(!app.settingsWindow && settingsClosePrompts == 2,
+                        "Cancel button allows discarding invalid edits");
+                auto originalSettings = app.settings;
+                // The isolated harness has no keyboard hook; save without shortcuts.
+                app.settings.toggle = app.settings.casing = app.settings.translit =
+                    app.settings.undo = app.settings.clipboard = app.settings.screenshot = L"";
+                app.settings.direct.assign(app.layouts.size(), L"");
+                ks::showSettings(app,false);
+                SendDlgItemMessageW(app.settingsWindow,208,BM_SETCHECK,
+                                    originalSettings.writeLog ? BST_UNCHECKED : BST_CHECKED,0);
+                settingsCloseChoice = IDYES;
+                SendMessageW(app.settingsWindow,WM_CLOSE,0,0);
+                require(!app.settingsWindow && settingsClosePrompts == 3 &&
+                        app.settings.writeLog != originalSettings.writeLog &&
+                        ks::loadSettings(app.data / L"settings.json",app.layouts).writeLog == app.settings.writeLog,
+                        "Yes saves settings to disk and applies them before closing");
+                app.settings = originalSettings;
+                ks::setLoggingEnabled(originalSettings.writeLog);
+                KillTimer(nullptr,timer);
+                settingsCloseChoice = IDCANCEL;
+                ks::showSettings(app,false);
+            }
             require(GetDlgItem(app.settingsWindow,258)!=nullptr,"sync available without local opt-in");
             // Mnemonics only target visible controls; show without taking foreground focus.
             ShowWindow(app.settingsWindow,SW_SHOWNOACTIVATE);
@@ -716,6 +824,10 @@ int main(int argc, char **argv) {
             require(IsWindowEnabled(app.settingsWindow),"closing sync restores parent");
             require(ks::InputRegressionAccess::staleSync(app,false),"in-flight sync cannot overwrite newer local edits");
             require(ks::InputRegressionAccess::staleSync(app,true),"disconnect discards in-flight downloaded profile");
+            require(ks::InputRegressionAccess::idleUndo(app),"idle cleanup retains available/busy Undo and frees expired Undo");
+            for(int mode=0;mode<3;++mode)
+                require(ks::InputRegressionAccess::completedSync(app,mode),
+                        "completed, failed and invalid sync release buffers but preserve conflict choices");
             require(ks::InputRegressionAccess::syncBackoff(app),"saving settings preserves authentication error backoff");
             SendMessageW(app.settingsWindow,WM_COMMAND,255,0);
             auto autoOptions=FindWindowW(L"KSwitcher.AutoOptions",nullptr);
@@ -774,6 +886,14 @@ int main(int argc, char **argv) {
             SendDlgItemMessageW(autoOptions,415,BM_SETCHECK,BST_CHECKED,0);
             SendMessageW(autoOptions,WM_COMMAND,IDOK,0);
             require(!IsWindow(autoOptions),"personal words accepted without file editing");
+            {
+                auto timer = SetTimer(nullptr,0,10,answerSettingsClose);
+                auto before = settingsClosePrompts;
+                SendMessageW(app.settingsWindow,WM_CLOSE,0,0);
+                KillTimer(nullptr,timer);
+                require(app.settingsWindow && settingsClosePrompts == before + 1,
+                        "accepted personal dictionary edits trigger unsaved settings warning");
+            }
             SendMessageW(app.settingsWindow,WM_COMMAND,255,0);
             autoOptions=FindWindowW(L"KSwitcher.AutoOptions",nullptr);
             ShowWindow(autoOptions,SW_HIDE);
@@ -792,6 +912,7 @@ int main(int argc, char **argv) {
             ks::showHistory(app,false);
             auto history=app.historyWindow;
             require(history&&!IsWindowVisible(history),"history layout tested without changing focus");
+            require(!GetDlgItem(history,105),"history creates no RichEdit control before formatted content is displayed");
             {
                 app.history=std::make_unique<ks::History>(temp/L"history-search");
                 app.history->add(ks::textClip(L"згенеруй приклад"),L"test",app.settings);
@@ -819,6 +940,27 @@ int main(int argc, char **argv) {
                 SetDlgItemTextW(history,101,L"");
                 require(pumpUntil(2),"clearing search restores history");
                 require(GetFocus()==originalFocus,"history search preserves focus");
+                SendDlgItemMessageW(history,102,LB_SETCURSEL,1,0);
+                ks::refreshHistory(app); // A result may still be in flight when closing.
+                SendDlgItemMessageW(history,101,WM_KEYDOWN,VK_ESCAPE,0);
+                require(!IsWindowVisible(history) && !GetDlgItem(history,105),
+                        "Escape closes history and leaves no RichEdit control");
+                SendMessageW(history,WM_TIMER,1,0); // KillTimer cannot retract a posted timer message.
+                require(pumpUntil(0),"closing history releases list strings");
+                auto until=GetTickCount64()+250;
+                while(GetTickCount64()<until) {
+                    MSG message{};
+                    while(PeekMessageW(&message,nullptr,0,0,PM_REMOVE)) {
+                        TranslateMessage(&message); DispatchMessageW(&message);
+                    }
+                    Sleep(5);
+                }
+                require(SendDlgItemMessageW(history,102,LB_GETCOUNT,0,0)==0,
+                        "late search results do not refill closed history");
+                ks::refreshHistory(app);
+                require(pumpUntil(2),"history reloads after releasing hidden rows");
+                require(SendDlgItemMessageW(history,102,LB_GETCURSEL,0,0)==1,
+                        "history retains selected record across close and reload");
             }
             auto childRect=[&](int id) { RECT r{}; GetWindowRect(GetDlgItem(history,id),&r); MapWindowPoints(nullptr,history,(POINT*)&r,2); return r; };
             RECT historyFrame{}; GetWindowRect(history,&historyFrame);

tests/integration.cpp

@@ -9,6 +9,7 @@ namespace ks
 {
 struct InputRegressionAccess
 {
+    static bool hasLast(App &app) { return app.last.has_value(); }
     static bool deferring(App &app)
     {
         std::lock_guard lock(app.stateMutex);
@@ -28,6 +29,8 @@ int pasteBehavior = 0;
 int enterPresses = 0;
 int copyFailuresRemaining = 0, copyRequests = 0;
 int droppedSelectionKeys = 0;
+bool trimCopiedSpaces = false;
+int trimmedCopies = 0;
 bool temporaryClipboardExcluded = true;
 bool clipboardAccessTimedOut = false;
 LRESULT CALLBACK observeEnter(HWND w, UINT message, WPARAM wp, LPARAM lp, UINT_PTR, DWORD_PTR)
@@ -76,10 +79,42 @@ LRESULT CALLBACK observeEnter(HWND w, UINT message, WPARAM wp, LPARAM lp, UINT_P
                 --copyFailuresRemaining;
                 return 0;
             }
+            if (trimCopiedSpaces)
+            {
+                auto result = DefSubclassProc(w, message, wp, lp);
+                // Native EDIT closes the clipboard in its copy handler, including
+                // our outer opening. Reopen it before changing its published data.
+                if (!OpenClipboard(w))
+                {
+                    clipboardAccessTimedOut = true;
+                    return result;
+                }
+                auto handle = GetClipboardData(CF_UNICODETEXT);
+                auto data = handle ? static_cast<const wchar_t *>(GlobalLock(handle)) : nullptr;
+                if (data)
+                {
+                    std::wstring copied(data);
+                    GlobalUnlock(handle);
+                    const auto originalSize = copied.size();
+                    while (!copied.empty() && copied.back() == L' ') copied.pop_back();
+                    auto replacement = GlobalAlloc(GMEM_MOVEABLE, (copied.size() + 1) * sizeof(wchar_t));
+                    auto output = GlobalLock(replacement);
+                    memcpy(output, copied.c_str(), (copied.size() + 1) * sizeof(wchar_t));
+                    GlobalUnlock(replacement);
+                    if (!EmptyClipboard() || !SetClipboardData(CF_UNICODETEXT, replacement))
+                    {
+                        GlobalFree(replacement);
+                        clipboardAccessTimedOut = true;
+                    }
+                    else if (copied.size() != originalSize) ++trimmedCopies;
+                }
+                return result;
+            }
         }
     }
     if (message == WM_PASTE && pasteBehavior)
     {
+        if (pasteBehavior == 3) { pasteBehavior = 0; return 0; }
         if (pasteBehavior == 2) SendMessageW(w, EM_REPLACESEL, TRUE, (LPARAM)L"other!");
         return 0;
     }
@@ -274,6 +309,8 @@ LRESULT CALLBACK procedure(HWND w, UINT msg, WPARAM wp, LPARAM lp)
                 app->settings.autoCorrect = true;
                 app->settings.switchLayout = true;
                 app->settings.autoLanguages = {L"en", L"ru"};
+                // Direct fixture mutations bypass applySettings' dictionary preload.
+                app->autoPredictor.configure(L"dictionaries", app->settings.autoLanguages);
                 app->settings.cycle = {app->layouts[en].id, app->layouts[ru].id};
                 ActivateKeyboardLayout(app->layouts[en].handle, 0);
                 prepare(L"ghbdtn ", false);
@@ -371,6 +408,7 @@ LRESULT CALLBACK procedure(HWND w, UINT msg, WPARAM wp, LPARAM lp)
                 require(text() == L"ghbdtn" && rows.back().outcome == L"Original text remained",
                         "blocked paste records original text remaining in the actual editor");
                 require(ks::readClipboard(app->window).text() == sentinel, "readback preserves clipboard after blocked paste");
+                require(!ks::InputRegressionAccess::hasLast(*app), "failed paste does not retain a fictional previous result");
                 pasteBehavior = 2;
                 prepare(L"ghbdtn", true);
                 app->transform(ks::Direct + ru);
@@ -381,6 +419,7 @@ LRESULT CALLBACK procedure(HWND w, UINT msg, WPARAM wp, LPARAM lp)
                 auto rows = ks::parseOperationLog(ks::wide(diagnosticLog()));
                 require(text() == L"other!" && rows.back().outcome == L"Readback differs",
                         "unexpected editor content records readback mismatch");
+                require(!ks::InputRegressionAccess::hasLast(*app), "changed readback cannot seed repeat conversion");
                 pasteBehavior = 0;
                 prepare(L"привет", true);
                 app->transform(ks::Direct + ru);
@@ -449,9 +488,95 @@ LRESULT CALLBACK procedure(HWND w, UINT msg, WPARAM wp, LPARAM lp)
                         details.find(L"Selection initial match=0") != details.npos &&
                         details.find(L"SelectPrevious") != details.npos,
                         "incident includes clipboard and selection stages");
-                finish();
+                pasteBehavior = 3;
+                prepare(L"=nhtdjuf", true);
+                app->transform(ks::Direct + ru);
+                stage = 49;
                 break;
             }
+            case 49:
+            {
+                require(text() == L"=тревога" && pasteBehavior == 0,
+                        "native Edit retries one ignored paste only while original remains selected");
+                require(ks::readClipboard(app->window).text() == sentinel, "native paste retry restores clipboard");
+                trimCopiedSpaces = true;
+                app->settings.writeLog = false;
+                prepare(L"OLDghbdtn  NEXT", false);
+                SendMessageW(field, EM_SETSEL, 11, 11);
+                record(L"ghbdtn  ");
+                app->transform(ks::Direct + ru);
+                break;
+            }
+            case 50:
+                require(text() == L"OLDпривет  NEXT", "trimmed clipboard recovery preserves two spaces and surrounding text without logging");
+                app->transform(ks::Direct + en);
+                break;
+            case 51:
+                require(text() == L"OLDghbdtn  NEXT", "repeat conversion preserves accessibility-proven spaces");
+                app->transform(ks::Undo);
+                break;
+            case 52:
+                require(text() == L"OLDпривет  NEXT", "undo preserves accessibility-proven spaces");
+                prepare(L"ghbdtn", false);
+                record(L"ghbdtn ");
+                app->transform(ks::Direct + ru);
+                break;
+            case 53:
+                require(text() == L"ghbdtn", "missing real space cannot be inferred from tracked keys");
+                prepare(L"wrong ", false);
+                record(L"ghbdtn ");
+                app->transform(ks::Direct + ru);
+                break;
+            case 54:
+                require(text() == L"wrong ", "unrelated selection remains rejected with trimmed clipboard");
+                app->settings.autoCorrect = true;
+                app->settings.autoLanguages = {L"en", L"ru"};
+                // The worker now shares the predictor's immutable dictionaries.
+                // This fixture changes settings directly instead of applySettings.
+                app->autoPredictor.configure(L"dictionaries", app->settings.autoLanguages);
+                app->autoCorrector = ks::AutoCorrector{};
+                ActivateKeyboardLayout(app->layouts[en].handle, 0);
+                prepare(L"ghbdtn ", false);
+                record(L"ghbdtn ");
+                app->transform(ks::AutoCorrect);
+                break;
+            case 55:
+                require(text() == L"привет ", "automatic correction recovers copied trailing space without logging");
+                app->transform(ks::Undo);
+                break;
+            case 56:
+            {
+                require(text() == L"ghbdtn ", "automatic correction undo retains recovered space");
+                require(ks::readClipboard(app->window).text() == sentinel, "space recovery restores clipboard");
+                pasteBehavior = 1;
+                prepare(L"ghbdtn ", false);
+                record(L"ghbdtn ");
+                app->transform(ks::Direct + ru);
+                break;
+            }
+            case 57:
+            {
+                require(text() == L"ghbdtn " && !ks::InputRegressionAccess::hasLast(*app),
+                        "recovered selection with blocked paste clears repeat state even without logging");
+                require(trimmedCopies >= 7, "fixture actually stripped spaces during recovery scenarios");
+                pasteBehavior = 0;
+                trimCopiedSpaces = false;
+                // User-selected middle range, followed by the same command with
+                // no selection: retain both surrounding text and trailing spaces.
+                prepare(L"OLDghbdtn  NEXT", false);
+                SendMessageW(field, EM_SETSEL, 3, 11);
+                app->transform(ks::Direct + ru);
+                break;
+            }
+            case 58:
+                require(text() == L"OLDпривет  NEXT", "explicit middle selection preserves surrounding text");
+                app->transform(ks::Direct + en);
+                break;
+            case 59:
+                require(text() == L"OLDghbdtn  NEXT", "hotkey without selection reconverts only the previous middle range");
+                require(ks::readClipboard(app->window).text() == sentinel, "selected and repeated conversions restore clipboard");
+                finish();
+                break;
             case 30:
             case 32:
             case 34:
@@ -559,6 +684,7 @@ LRESULT CALLBACK procedure(HWND w, UINT msg, WPARAM wp, LPARAM lp)
                 app->settings.autoCorrect = true;
                 app->settings.switchLayout = true;
                 app->settings.autoLanguages = {L"en", L"ru"};
+                app->autoPredictor.configure(L"dictionaries", app->settings.autoLanguages);
                 app->settings.cycle = {app->layouts[en].id, app->layouts[ru].id};
                 app->autoCorrector = ks::AutoCorrector{};
                 ActivateKeyboardLayout(app->layouts[en].handle, 0);
@@ -608,6 +734,7 @@ LRESULT CALLBACK procedure(HWND w, UINT msg, WPARAM wp, LPARAM lp)
                 });
                 require(uk != app->layouts.end(), "Ukrainian layout available for punctuation-key regression");
                 app->settings.autoLanguages = {L"en", L"uk"};
+                app->autoPredictor.configure(L"dictionaries", app->settings.autoLanguages);
                 app->settings.cycle = {app->layouts[en].id, uk->id};
                 app->settings.autoWords[L"uk"] = {L"робить"};
                 app->autoCorrector = ks::AutoCorrector{};
@@ -853,7 +980,7 @@ int main(int argc, char **argv)
             field =
                 CreateWindowW(L"EDIT", L"", WS_CHILD | WS_VISIBLE | WS_BORDER | ES_MULTILINE | ES_WANTRETURN,
                               20, 20, 590, 230, host, nullptr, cls.hInstance, nullptr);
-            deadline = GetTickCount64() + 30000;
+            deadline = GetTickCount64() + 60000;
             SetWindowSubclass(field, observeEnter, 1, 0);
             if (typosOnly || (argc > 1 && std::string(argv[1]) == "--typing-only"))
                 stage = 20;

tests/ocr.cpp

@@ -59,6 +59,24 @@ int main(int argc, char **argv)
             app.settings.history = true;
             app.history->add(clip, L"OCR fixture", app.settings);
             auto id = app.history->entries().front().id;
+            auto isolated = app.history->recognizeImage(id, config);
+            if (isolated != text) throw std::runtime_error("Helper and in-process OCR results differ");
+            bool cancelled = false;
+            try { app.history->recognizeImage(id, config, [] { return true; }); }
+            catch (const std::exception &) { cancelled = true; }
+            if (!cancelled) throw std::runtime_error("Cancelled OCR request was executed");
+            auto invalid = config;
+            invalid.useTesseract = true;
+            invalid.tesseractPath = (temp / L"missing-tesseract.exe").wstring();
+            bool failed = false;
+            try { app.history->recognizeImage(id, invalid); }
+            catch (const std::exception &) { failed = true; }
+            if (!failed || app.history->entries().front().ocrState != 1)
+                throw std::runtime_error("Failed helper modified history metadata");
+            for (const auto &file : std::filesystem::directory_iterator(temp / L"history"))
+                if (file.path().filename().wstring().starts_with(L"ocr-"))
+                    throw std::runtime_error("OCR helper left temporary files");
+            std::cout << "PASS isolated OCR equivalence, cancellation, failure and encrypted IPC cleanup\n";
             if (tesseract)
             {
                 app.history->saveOcr(id, L"old Windows result", app.settings);

tests/screenshot_registration.cpp

@@ -5,9 +5,11 @@
 static std::wstring programs;
 static std::wstring activationExecutable, activationCommand;
 static int activationCalls{};
+static DWORD launchFlags{}; static bool inheritsHandles{};
 static BOOL WINAPI testCreateProcess(LPCWSTR path, LPWSTR command, LPSECURITY_ATTRIBUTES,
-    LPSECURITY_ATTRIBUTES, BOOL, DWORD, LPVOID, LPCWSTR, LPSTARTUPINFOW, LPPROCESS_INFORMATION)
+    LPSECURITY_ATTRIBUTES, BOOL inherit, DWORD flags, LPVOID, LPCWSTR, LPSTARTUPINFOW, LPPROCESS_INFORMATION)
 {
+    launchFlags=flags; inheritsHandles=inherit;
     ++activationCalls; activationExecutable=path; activationCommand=command;
     SetLastError(ERROR_CANCELLED); return FALSE; // Inspect activation without starting any program.
 }
@@ -55,6 +57,14 @@ int main()
         valid=id.vt==VT_CLSID && *id.puuid==ks::ActivatorId; PropVariantClear(&id);
         if(!valid) throw std::runtime_error("shortcut activator missing");
         ks::registerScreenshotNotifications(); // Registration is safe to repeat.
+        bool launchFailed=false;
+        try { ks::startScreenshotNotificationRegistration(); }
+        catch(const std::exception &) { launchFailed=true; }
+        if(!launchFailed || activationExecutable!=helper.wstring() ||
+           activationCommand!=L"\""+helper.wstring()+L"\" --register-notifications" ||
+           !(launchFlags&CREATE_NO_WINDOW) || inheritsHandles)
+            throw std::runtime_error("registration must launch the sibling helper and propagate failure");
+        activationCalls=0;
         ks::Activator activator(helper.wstring(),false);
         activator.Activate(L"HrynCo.KSwitcher.Screenshot",L"check-update",nullptr,0);
         auto main=(helper.parent_path()/L"KSwitcher.exe").wstring();

tests/screenshot_ui.cpp

@@ -225,6 +225,17 @@ int main(int argc, char **argv)
             require(c.zoom>zoom && std::abs(before.x-after.x)<=1 && std::abs(before.y-after.y)<=1,
                     "Ctrl+wheel zoom keeps image point under cursor");
             require(!c.history.canUndo(),"zoom does not add image edits to undo history");
+            // A fixed zoom can still fit inside a high-DPI editor. Size the
+            // fixture from the actual viewport, with room for the tested drag
+            // on both axes, then start from a centered view.
+            const double panZoom=std::max({1.0,
+                double(c.canvas.right-c.canvas.left+128)/(c.view.right-c.view.left),
+                double(c.canvas.bottom-c.canvas.top+128)/(c.view.bottom-c.view.top)});
+            ks::zoomCanvas(window,c,panZoom,center);
+            c.panX=c.panY=0; ks::layout(window,c);
+            require(c.view.left+15<c.canvas.left && c.view.top+10<c.canvas.top &&
+                    c.view.right>c.canvas.right && c.view.bottom>c.canvas.bottom,
+                    "pan fixture has drag clearance on both axes within the supported zoom range");
             auto view=c.view;
             SendMessageW(window,WM_MBUTTONDOWN,MK_MBUTTON,MAKELPARAM(center.x,center.y));
             SendMessageW(window,WM_MOUSEMOVE,MK_MBUTTON,MAKELPARAM(center.x+15,center.y+10));
@@ -443,8 +454,16 @@ int main(int argc, char **argv)
             c.marks={{{20,20},{120,20},0}};
             require(ks::actionCursor(c,{0,ks::MarkPart::Body},true)==LoadCursorW(nullptr,IDC_SIZEALL),"move cursor overrides drawing tool");
             require(ks::actionCursor(c,{0,ks::MarkPart::Rotation},true)==LoadCursorW(nullptr,IDC_HAND),"rotation cursor overrides drawing tool");
-            require(ks::actionCursor(c,{0,ks::MarkPart::End},true)==LoadCursorW(nullptr,IDC_SIZEWE),"endpoint resize overrides drawing tool");
+            for(auto part:{ks::MarkPart::Start,ks::MarkPart::End,ks::MarkPart::Radius,
+                           ks::MarkPart::Label,ks::MarkPart::Vertex0,ks::MarkPart::Vertex1,ks::MarkPart::Vertex2})
+                require(ks::actionCursor(c,{0,part},true)==LoadCursorW(nullptr,IDC_SIZEALL),
+                        "freely movable handles use four-direction cursor for every drawing tool");
             require(ks::actionCursor(c,{0,ks::MarkPart::Thickness},true)==LoadCursorW(nullptr,IDC_SIZENS),"thickness resize is perpendicular to line");
+            c.marks[0].to={20,120};
+            require(ks::actionCursor(c,{0,ks::MarkPart::End},true)==LoadCursorW(nullptr,IDC_SIZEALL),
+                    "vertical line endpoint still moves in both axes");
+            require(ks::actionCursor(c,{0,ks::MarkPart::Thickness},true)==LoadCursorW(nullptr,IDC_SIZEWE),
+                    "vertical line thickness retains horizontal resize cursor");
         }
         c.marks.clear(); SendMessageW(window,WM_COMMAND,27,0);
         wchar_t windowTitle[128]{}; GetWindowTextW(window,windowTitle,128);

tests/tests.cpp

@@ -4,6 +4,7 @@
 #include "richtext.h"
 #include "storage.h"
 #include "diagnostics.h"
+#include "json.hpp"
 #include <algorithm>
 #include <iostream>
 #include <map>
@@ -23,20 +24,6 @@ void rejects(const std::function<void()> &f, const char *name)
     bool thrown = false;
     try
     {
-        {
-            std::map<std::wstring,int> previews;
-            std::set<std::wstring> visible;
-            for(int i=0;i<40;++i) previews[std::to_wstring(i)]=i;
-            for(int i=0;i<8;++i) visible.insert(std::to_wstring(i));
-            ks::trimHistoryPreviews(previews,visible);
-            require(previews.size()==32,"preview cache stays bounded");
-            for(const auto &id:visible) require(previews.contains(id),"visible preview survives eviction");
-            for(int i=0;i<40;++i) { auto id=std::to_wstring(i); previews[id]=i; visible.insert(id); }
-            ks::trimHistoryPreviews(previews,visible);
-            require(previews.size()==40,"tall viewport does not thrash visible previews");
-            visible.clear(); ks::trimHistoryPreviews(previews,visible);
-            require(previews.size()==32,"cache shrinks after leaving tall viewport");
-        }
         f();
     }
     catch (...)
@@ -60,6 +47,34 @@ int main(int argc, char **argv)
     }
     try
     {
+        // Byte budgets must retain visible entries even when they alone exceed the budget.
+        {
+            std::map<std::wstring, size_t> cache{{L"a", 800}, {L"b", 800}, {L"c", 100}};
+            std::set<std::wstring> visible{L"b"};
+            auto weight=[](size_t bytes) { return bytes; };
+            ks::trimHistoryPreviews(cache, visible, 32, 1000, weight);
+            require(cache.size()==2 && cache.contains(L"b") && cache.contains(L"c"),
+                    "byte budget evicts offscreen previews below count limit");
+            ks::trimHistoryPreviews(cache, visible, 32, 100, weight);
+            require(cache.size()==1 && cache.contains(L"b"), "oversized visible preview never thrashes");
+            visible.clear();
+            ks::trimHistoryPreviews(cache, visible, 32, 100, weight);
+            require(cache.empty(), "oversized preview is freed after leaving viewport");
+        }
+        {
+            std::map<std::wstring,int> previews;
+            std::set<std::wstring> visible;
+            for(int i=0;i<40;++i) previews[std::to_wstring(i)]=i;
+            for(int i=0;i<8;++i) visible.insert(std::to_wstring(i));
+            ks::trimHistoryPreviews(previews,visible);
+            require(previews.size()==32,"preview cache stays bounded");
+            for(const auto &id:visible) require(previews.contains(id),"visible preview survives eviction");
+            for(int i=0;i<40;++i) { auto id=std::to_wstring(i); previews[id]=i; visible.insert(id); }
+            ks::trimHistoryPreviews(previews,visible);
+            require(previews.size()==40,"tall viewport does not thrash visible previews");
+            visible.clear(); ks::trimHistoryPreviews(previews,visible);
+            require(previews.size()==32,"cache shrinks after leaving tall viewport");
+        }
         {
             ks::DiagnosticJson record{{"attempt", "42"}, {"process", "editor.exe"}, {"command", "Convert / cycle"},
                 {"source", "English"}, {"target", "Ukrainian"}, {"outcome", "Original text remained"},
@@ -99,6 +114,10 @@ int main(int argc, char **argv)
                 "large diagnostic selections are explicitly truncated");
         STARTUPINFOW startup{sizeof(startup)};
         ks::DiagnosticBuffer diagnostics;
+        diagnostics.record(L"idle-expiry", false, 0);
+        require(diagnostics.expire(30000)==0,"diagnostics remain available at expiry boundary");
+        require(diagnostics.expire(30001)==1,"idle expiry releases context without another log event");
+        require(diagnostics.expire(60000)==0,"repeated idle expiry is safe");
         require(diagnostics.record(L"successful-attempt", false, 100).empty(),
                 "successful diagnostics stay in memory");
         auto incident = diagnostics.record(L"failed-attempt", true, 200);
@@ -171,6 +190,8 @@ int main(int argc, char **argv)
                 "HTML entities and Unicode survive without script text");
         require((effects(0, 6) & CFE_BOLD) != 0, "inline CSS bold is rendered");
         auto plain = ks::textClip(L"{\\literal} Привіт");
+        require(ks::richPreview(plain, false).empty(), "plain history preview does not require RichEdit");
+        require(!ks::richPreview(styled, false).empty(), "formatted history preview retains HTML rendering");
         ks::setRichText(rich, ks::richPreview(plain));
         GetWindowTextW(rich, rendered, 256);
         require(std::wstring(rendered) == plain.text(), "plain Unicode and RTF metacharacters are escaped");
@@ -217,6 +238,26 @@ int main(int argc, char **argv)
         require(!autoSettings.autoCorrect, "auto-correction defaults off");
         autoSettings.cycle = {L"en", L"uk"};
         corrector.configure(L"dictionaries", autoSettings.autoLanguages);
+        {
+            ks::AutoCorrector consumer;
+            consumer.shareDictionaries(corrector);
+            require(consumer.suggest(L"ghbdsn ", 0, layouts, autoSettings).has_value(),
+                    "shared dictionaries produce the same correction");
+            consumer.reject(L"ghbdsn");
+            consumer.shareDictionaries(corrector);
+            require(!consumer.suggest(L"ghbdsn ", 0, layouts, autoSettings),
+                    "refreshing shared dictionaries preserves consumer undo rejections");
+            require(corrector.suggest(L"ghbdsn ", 0, layouts, autoSettings).has_value(),
+                    "consumer rejections do not affect the predictor");
+            ks::AutoCorrector retained;
+            retained.shareDictionaries(corrector);
+            corrector.configure({}, {});
+            require(retained.suggest(L"ghbdsn ", 0, layouts, autoSettings).has_value(),
+                    "in-flight dictionary snapshot survives source reset");
+            consumer.shareDictionaries(corrector);
+            require(consumer.memoryBytes() == 0, "disabled correction releases consumer dictionaries");
+            corrector.shareDictionaries(retained);
+        }
         {
             auto options = autoSettings;
             options.autoTypos = true;
@@ -545,6 +586,20 @@ int main(int argc, char **argv)
             require(!ambiguous.suggest(L"hell ", 0, layouts, options), "frequency filter does not conceal ambiguous typo targets");
         }
         ks::Pixels pixels{2, 1, {10, 20, 30, 255, 40, 50, 60, 255}};
+        {
+            auto png = ks::encodePng(pixels);
+            ks::Clip encoded{{{0, L"PNG", png}}};
+            for (int i=0; i<3; ++i) {
+                auto decoded=ks::decodeImage(encoded);
+                require(decoded.bgra==pixels.bgra && decoded.width==2 && decoded.height==1,
+                        "borrowed PNG stream preserves decoded pixels on repeated reads");
+                require(encoded.formats[0].data==png,"PNG decoder never modifies the borrowed input");
+            }
+            ks::Clip fallback{{{0,L"PNG",{}},ks::imageDib(pixels)}};
+            require(ks::decodeImage(fallback).bgra==pixels.bgra,"empty PNG falls back to DIB");
+            ks::Clip invalid{{{0,L"PNG",{1,2,3}}}};
+            rejects([&] { ks::decodeImage(invalid); },"invalid borrowed PNG fails safely");
+        }
         ks::Clip firstImage{{ks::imageDib(pixels), {0, L"Ole Private Data", {1, 2, 3}}}};
         auto thumbnail = ks::decodeImage(firstImage, 1, 1);
         require(thumbnail.width == 1 && thumbnail.height == 1 && thumbnail.bgra.size() == 4,
@@ -583,6 +638,55 @@ int main(int argc, char **argv)
                     "Snipping Tool republish retains one pinned history entry");
             history.add(changedImage, L"SnippingTool", defaults);
             require(history.entries().size() == 2, "a new screenshot is retained");
+            auto copiedText = ks::textClip(L"text after screenshot");
+            history.add(copiedText, L"Editor", defaults);
+            history.add(copiedText, L"Editor", defaults);
+            require(history.entries().size() == 3 && !history.entries().front().image,
+                    "text after screenshot is retained and consecutive text duplicates are skipped");
+            history.add(changedImage, L"SnippingTool", defaults);
+            history.add(changedImage, L"SnippingTool", defaults);
+            require(history.entries().size() == 4 && history.entries().front().image,
+                    "image after text is retained and consecutive image duplicates are skipped");
+            history.add(withText, L"Editor", defaults);
+            require(history.entries().size() == 5,
+                    "mixed image and text payload is not discarded by metadata prefilter");
+        }
+        {
+            auto folder = temp / L"fingerprints";
+            ks::Settings defaults;
+            ks::History history(folder);
+            history.add(firstImage, L"test", defaults);
+            auto id = history.entries().front().id;
+            history.pin(id);
+            history.saveOcr(id, L"retained OCR", defaults);
+            ks::History reopened(folder);
+            require(reopened.entries().front().contentHash.size() == 64,
+                    "SHA-256 fingerprint survives encrypted index reload");
+            // Deny payload reads: duplicates must still be detected using only the index.
+            auto handle = CreateFileW((folder / (id + L".dat")).c_str(), GENERIC_READ, 0, nullptr,
+                                      OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, nullptr);
+            require(handle != INVALID_HANDLE_VALUE, "lock image payload for no-read regression");
+            reopened.add(firstImage, L"test", defaults);
+            reopened.add(secondImage, L"test", defaults);
+            reopened.add(recoded, L"test", defaults);
+            CloseHandle(handle);
+            require(reopened.entries().size() == 1 && reopened.entries().front().pinned &&
+                    reopened.ocrText(id) == std::optional<std::wstring>(L"retained OCR"),
+                    "exact, OLE and pixel-equivalent duplicates need no payload read and retain pin/OCR");
+            auto index = nlohmann::json::parse(ks::unprotect(ks::readFile(folder / L"index.dat", 1024*1024)));
+            for (auto &entry : index)
+                for (auto key : {"fingerprintVersion", "contentHash", "imageHash", "pixelHash"}) entry.erase(key);
+            auto legacy = index.dump();
+            ks::atomicWrite(folder / L"index.dat", ks::protect(ks::Bytes(legacy.begin(), legacy.end())));
+            ks::History migrated(folder);
+            migrated.add(secondImage, L"test", defaults);
+            ks::History persisted(folder);
+            require(persisted.entries().size() == 1 && persisted.entries().front().contentHash.size() == 64,
+                    "legacy duplicate migrates fingerprints without adding or losing an entry");
+            persisted.add(changedImage, L"test", defaults);
+            require(persisted.entries().size() == 2, "pixel fingerprint preserves genuinely changed images");
+            persisted.add(firstImage, L"test", defaults);
+            require(persisted.entries().size() == 3, "hash deduplication remains consecutive rather than global");
         }
         ks::Settings settings;
         settings.writeLog = false;

tools/measure-memory-components.ps1

@@ -0,0 +1,61 @@
+param([ValidateRange(1,20)][int]$Runs=3,[ValidateRange(100,10000)][int]$SettleMilliseconds=1500)
+# Private resident pages are counted externally, so the measurement buffer is
+# allocated in PowerShell, not in the measured process. Never trim working sets.
+$ErrorActionPreference='Stop'
+$root=Split-Path $PSScriptRoot -Parent
+$output=Join-Path $root 'build/memory-components'
+New-Item -ItemType Directory -Force $output | Out-Null
+$exe=Join-Path $output 'probe.exe'
+& "$root/.tools/w64devkit/bin/g++.exe" -std=c++20 -Os -static -s -DUNICODE -D_UNICODE -D_WIN32_WINNT=0x0A00 "$PSScriptRoot/memory-components.cpp" -o $exe -lole32 -loleaut32 -lshell32 -lpropsys -lshlwapi -luuid -luiautomationcore
+if($LASTEXITCODE) { throw 'Probe compilation failed' }
+Add-Type @'
+using System;
+using System.Runtime.InteropServices;
+public static class ComponentWorkingSet {
+ [DllImport("psapi.dll", SetLastError=true)] static extern bool QueryWorkingSet(IntPtr process,IntPtr buffer,int size);
+ public static long PrivateBytes(IntPtr process) {
+  int size=4*1024*1024;
+  IntPtr buffer=Marshal.AllocHGlobal(size);
+  try {
+   if(!QueryWorkingSet(process,buffer,size)) throw new System.ComponentModel.Win32Exception();
+   long count=Marshal.ReadIntPtr(buffer).ToInt64(), pages=0;
+   if(count>(size/IntPtr.Size)-1) throw new InvalidOperationException("Working set buffer is too small");
+   for(int i=0;i<count;i++) if((Marshal.ReadIntPtr(buffer,(i+1)*IntPtr.Size).ToInt64() & 256)==0) pages++;
+   return pages*Environment.SystemPageSize;
+  } finally { Marshal.FreeHGlobal(buffer); }
+ }
+}
+'@
+$rows=[Collections.Generic.List[object]]::new()
+foreach($run in 1..$Runs) {
+ foreach($mode in @('baseline','sta','mta','shell','uia','focused','combined')) {
+  $start=[Diagnostics.ProcessStartInfo]::new($exe,$mode)
+  $start.UseShellExecute=$false; $start.CreateNoWindow=$true
+  $start.RedirectStandardOutput=$true; $start.RedirectStandardInput=$true; $start.RedirectStandardError=$true
+  $process=[Diagnostics.Process]::Start($start)
+  $errors=$process.StandardError.ReadToEndAsync()
+  try {
+   foreach($expected in @('baseline','com','active','released','uninitialized')) {
+    $pending=$process.StandardOutput.ReadLineAsync()
+    if(!$pending.Wait(15000)) { throw "Timeout: $mode/$expected" }
+    $phase=$pending.Result
+    if($phase -ne $expected) { throw "Unexpected phase '$phase', expected $expected" }
+    Start-Sleep -Milliseconds $SettleMilliseconds
+    $process.Refresh()
+    $rows.Add([pscustomobject]@{Run=$run;Mode=$mode;Phase=$phase;PrivateBytes=$process.PrivateMemorySize64;PrivateWorkingSet=[ComponentWorkingSet]::PrivateBytes($process.Handle);WorkingSet=$process.WorkingSet64;Threads=$process.Threads.Count;Modules=@($process.Modules | ForEach-Object ModuleName)})
+    $process.StandardInput.Write("`n"); $process.StandardInput.Flush()
+   }
+   if(!$process.WaitForExit(15000)) { throw 'Exit timeout' }
+   if($process.ExitCode) { throw "Probe failed: $($errors.Result)" }
+   $errors.Result | Set-Content (Join-Path $output "$run-$mode.txt")
+  } finally {
+   if(!$process.HasExited) { $process.Kill(); $process.WaitForExit() }
+   $process.Dispose()
+   $rows | ConvertTo-Json -Depth 5 | Set-Content (Join-Path $output 'results.json')
+  }
+  Write-Host "Completed $run/$Runs $mode"
+ }
+}
+$rows | Group-Object Mode,Phase | ForEach-Object {
+ [pscustomobject]@{Case=$_.Name;PrivateMiB=[math]::Round(($_.Group.PrivateBytes | Measure-Object -Average).Average/1MB,3);PrivateWorkingSetMiB=[math]::Round(($_.Group.PrivateWorkingSet | Measure-Object -Average).Average/1MB,3)}
+} | Format-Table

tools/memory-components.cpp

@@ -0,0 +1,65 @@
+// Standalone attribution probe. No clipboard, registry or user input mutations.
+#include <windows.h>
+#include <shlobj.h>
+#include <propkey.h>
+#include <propvarutil.h>
+#include <uiautomation.h>
+#include <cstdio>
+#include <cstring>
+#include <cstdlib>
+
+static void check(HRESULT hr) {
+    if (FAILED(hr)) { fprintf(stderr,"HRESULT=%08lx\n",(unsigned long)hr); exit(2); }
+}
+static void phase(const char *name) {
+    printf("%s\n",name); fflush(stdout);
+    if (getchar()==EOF) exit(3);
+}
+int main(int argc,char **argv) {
+    const char *mode=argc>1?argv[1]:"baseline";
+    const bool baseline=!strcmp(mode,"baseline");
+    const bool shell=!strcmp(mode,"shell") || !strcmp(mode,"combined");
+    const bool uia=!strcmp(mode,"uia") || !strcmp(mode,"focused") || !strcmp(mode,"combined");
+    phase("baseline");
+    if(!baseline) check(CoInitializeEx(nullptr,!strcmp(mode,"sta") || shell ? COINIT_APARTMENTTHREADED : COINIT_MULTITHREADED));
+    phase("com");
+    IShellLinkW *link{}; IPropertyStore *store{}; IPersistFile *file{};
+    IUIAutomation2 *automation{}; IUIAutomationElement *element{}; IUIAutomationTextPattern *pattern{};
+    wchar_t temporary[MAX_PATH]{},shortcut[MAX_PATH]{},exe[MAX_PATH]{};
+    if(shell) {
+        check(CoCreateInstance(CLSID_ShellLink,nullptr,CLSCTX_INPROC_SERVER,IID_PPV_ARGS(&link)));
+        GetModuleFileNameW(nullptr,exe,MAX_PATH);
+        check(link->SetPath(exe)); check(link->SetIconLocation(exe,0));
+        check(link->QueryInterface(IID_PPV_ARGS(&store)));
+        PROPVARIANT value{}; check(InitPropVariantFromString(L"KSwitcher.MemoryProbe",&value));
+        check(store->SetValue(PKEY_AppUserModel_ID,value)); PropVariantClear(&value);
+        GUID id{0xe3f78047,0xf0ad,0x49b6,{0x90,0x74,0x41,0x19,0x31,0x70,0x61,0x67}};
+        value.vt=VT_CLSID; value.puuid=&id;
+        check(store->SetValue(PKEY_AppUserModel_ToastActivatorCLSID,value)); check(store->Commit());
+        PWSTR programs{}; check(SHGetKnownFolderPath(FOLDERID_Programs,0,nullptr,&programs)); CoTaskMemFree(programs);
+        GetTempPathW(MAX_PATH,temporary); if(!GetTempFileNameW(temporary,L"ksm",0,shortcut)) return 4;
+        check(link->QueryInterface(IID_PPV_ARGS(&file))); check(file->Save(shortcut,TRUE));
+    }
+    if(uia) {
+        check(CoCreateInstance(CLSID_CUIAutomation8,nullptr,CLSCTX_INPROC_SERVER,IID_PPV_ARGS(&automation)));
+        check(automation->put_ConnectionTimeout(200)); check(automation->put_TransactionTimeout(200));
+        if(strcmp(mode,"uia")) {
+            HRESULT focused=automation->GetFocusedElement(&element);
+            fprintf(stderr,"focus=%08lx\n",(unsigned long)focused);
+            if(SUCCEEDED(focused) && element) {
+                BOOL password=TRUE,enabled=FALSE; CONTROLTYPEID type{};
+                element->get_CurrentIsPassword(&password); element->get_CurrentIsEnabled(&enabled); element->get_CurrentControlType(&type);
+                fprintf(stderr,"type=%d enabled=%d protected=%d\n",type,enabled,password);
+                if(!password) fprintf(stderr,"pattern=%08lx\n",(unsigned long)element->GetCurrentPatternAs(UIA_TextPatternId,IID_PPV_ARGS(&pattern)));
+            }
+        }
+    }
+    phase("active");
+    if(pattern) pattern->Release(); if(element) element->Release(); if(automation) automation->Release();
+    if(file) file->Release(); if(store) store->Release(); if(link) link->Release();
+    if(shortcut[0]) DeleteFileW(shortcut);
+    phase("released");
+    if(!baseline) { CoFreeUnusedLibrariesEx(0,0); CoUninitialize(); }
+    phase("uninitialized");
+    return 0;
+}