Release v0.6.29: clear clipboard history from its window

CMakeLists.txt

@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.24)
-project(KSwitcher VERSION 0.6.27 LANGUAGES CXX RC)
+project(KSwitcher VERSION 0.6.29 LANGUAGES CXX RC)
 if(NOT WIN32)
   message(FATAL_ERROR "KSwitcher uses native Windows APIs")
 endif()

README.md

@@ -321,6 +321,10 @@ 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
@@ -336,7 +340,14 @@ the executable's directory is not writable. Each clipboard payload is an encrypt
 only bounded previews/metadata stay in memory. Image data is loaded on demand and released when
 the history popup is hidden. Settings **Write log** (`writeLog`, enabled by default) controls all
 log writes. Disabling it also clears diagnostic context from memory; existing log files remain.
-Diagnostic stages stay in a memory buffer of at most 40 events for 30 seconds.
+Diagnostic stages stay in a memory buffer of at most 128 events for 30 seconds.
+Selection diagnostics include the expected text, each copied candidate before and after suffix
+recovery, paced Shift+Left progress or batch delivery counts, and clipboard sequence changes,
+retry counts and elapsed times. Focus, caret geometry and keyboard layout are recorded when
+Windows exposes them; selection offsets are available for native EDIT controls and explicitly
+marked unavailable for other editors. Input interruptions identify keyboard, mouse, settings
+or layout-refresh events during an operation. Failed selection verification includes the expected
+selection and actual copied text in the operation details, without implying that a paste occurred.
 Only problem operations write a structured summary to `kswitcher.log`, with their preceding
 context. Successful operations stay in that bounded memory buffer and are included only when
 a subsequent problem flushes it; they do not create separate rows. Flushed context is discarded. Ordinary application
@@ -404,6 +415,10 @@ reverse-proxy URL prefixes, MFA login flows and other providers are not implemen
 
 Enable synchronization and choose **Save / Sign in / Sync**. The dialog saves connection changes
 immediately; the main Settings window's Save/Cancel does not control this separate configuration.
+When synchronization is disabled, connection fields and sync actions are inactive. Check **Enable
+synchronization** to make them available. To disable an existing connection, uncheck it and click
+**Save**; this preserves the saved connection and password without starting a sync request.
+**Disconnect / forget password** remains available while synchronization is disabled.
 A blank password keeps the existing Windows credential for that server, login mount and username.
 The password is saved in Windows Credential Manager, not in settings exports, logs or the remote
 profile. HTTPS certificate validation is mandatory and redirects are refused. Login tokens are
@@ -414,11 +429,15 @@ saved credential. A request already sent to the server may still complete; its d
 will not be applied after the connection changes. Old credentials for other connection identities
 can be removed in Windows Credential Manager under `KSwitcher.Sync/`.
 
-First connection is deliberately explicit:
+On the first connection, **Save / Sign in / Sync** merges the existing profiles without
+requiring a whole-profile replacement. Independent entries (such as snippets, exclusions and
+replacement pairs) are combined. Different values for the same setting remain on their respective
+sides and appear in **Resolve individual conflicts...**; no value is guessed without a common history.
+Nonconflicting changes synchronize immediately, and unresolved conflicts survive subsequent syncs.
 
 - **Upload local** creates the remote profile or replaces it with this PC's saved shared settings.
 - **Download remote** replaces this PC's shared settings with the server profile.
-- If both profiles are identical, ordinary Sync can establish the baseline without a replacement.
+- If the server has no profile yet, choose **Upload local** to create it.
 - Unsaved edits in Settings are not synchronized. Close and reopen Settings after a download;
   the existing stale-editor check prevents an old Settings window overwriting downloaded changes.
 
@@ -453,8 +472,14 @@ Deleted server versions are not silently recreated.
 Hotkeys, snippets, application exclusions, layout order, conversion, screenshot and autocorrection
 preferences are shared. Startup/elevation, keep-awake, logging, history enablement/limits,
 Tesseract executable/engine selection, connection details and credentials stay local. Clipboard
-history, screenshots and dictionary files are never uploaded. Missing keyboard layouts block
-applying a remote profile until those Windows layouts are installed, preventing lost bindings.
+history, screenshots and dictionary files are never uploaded. Full synchronization identifies
+missing keyboard layouts by language (when Windows can identify it) and exact ID.
+Install the same layout variant, or select **Keep this PC's layouts and layout shortcuts (sync
+other settings)** and click **Save / Sign in / Sync**. This device-local option keeps the entire
+local layout cycle and its direct shortcuts unchanged while synchronizing the other shared settings.
+The server's layout cycle and direct shortcuts are preserved on automatic sync and explicit Upload;
+Download also keeps the local layout configuration. Later syncs cannot erase missing server layouts
+just because this PC does not have them installed. Uncheck the option to resume full layout sync.
 Settings are JSON inside OpenBao; this is not end-to-end encryption from the vault administrator.
 
 The last common profile (`sync-base.bin`) and the settings preceding the most recent downloaded
@@ -506,13 +531,40 @@ Alternatively open this directory as a CMake project in Visual Studio with the C
 and Windows SDK installed, or use CMake with a Windows GCC toolchain. CMake/MSVC is provided but the
 verified local build uses GCC/w64devkit.
 
-## Automatic layout correction (experimental)
+## Automatic correction (experimental)
 
-Enable **Automatically correct layout (experimental)** in Settings, then use **Auto-correction
+Enable **Automatic correction (experimental)** in Settings, then use **Auto-correction
 options…** to select dictionary languages and edit excluded applications or words to never correct.
 The feature is off by default. English and Ukrainian are selected initially; Russian is optional.
 Target layouts must also be enabled in the layout cycle.
 
+### Custom replacements and spelling typos
+
+Two optional modes in **Auto-correction options…** extend layout correction. Both are off by
+default and require the main **Automatic correction (experimental)** checkbox to be enabled.
+
+- **Use custom replacements**: enter one `typo=correction` pair per line, for example
+  `првиіт=привіт` or `helo=hello`. Entries are normalized to lowercase; duplicate source words
+  are rejected. Each side must contain 1–32 letters of the same supported language, without
+  spaces or punctuation. Explicit pairs take priority over dictionary recognition, including
+  already valid words, and do not require dictionary membership or satisfy the frequency limit.
+- **Correct spelling typos using dictionaries**: checks unknown words in the current language
+  after no layout correction is found. It accepts exactly one dictionary candidate reachable
+  by inserting, deleting or replacing one letter, or swapping two adjacent letters. Both input
+  and target must have at least four letters. Multiple candidates leave the input unchanged,
+  even if a frequency limit would exclude one of them. Personal dictionary words participate.
+  This is word-level spelling correction, not grammar or sentence-context correction.
+
+Both modes run after Space, preserve surrounding punctuation and an initial capital, and keep
+the current layout. The selected dictionary languages, enabled layout cycle, minimum input
+length, excluded applications, never-correct list, protected fields and Undo behavior apply.
+ALL CAPS, mixed-case identifiers, numbers, URLs and email addresses are skipped. A replacement
+is applied once, without chaining. Click **OK**, then **Save** in Settings; pairs and switches
+are included in settings export/import and synchronization. Undo restores the original word
+and suppresses its correction until restart.
+
+### Layout correction and shared options
+
 **Characters before a word** and **Characters after a word** configure punctuation to preserve around
 the corrected word. Enter characters directly, without spaces or separators; a comma or semicolon
 is itself a character. Defaults include parentheses, square/curly brackets, quotation marks and common

Release/README.md

@@ -1,23 +1,23 @@
 # Latest Windows release
 
-## v0.6.27 — 2026-11-02
+## v0.6.29 — 2026-11-02
 
 ## Changes
-- Tray and clipboard context menus support underlined access keys. Press the letter while a menu is open (S for Settings, X for Exit).
-- Alt+letter activates buttons and checkboxes in Settings, Snippets, Logs, synchronization/conflict, OCR and dictionary dialogs. Selected field labels also move focus to their input.
-- Clipboard history supports Alt+letter for its actions and search while retaining Enter, Shift+Enter and Ctrl+digit shortcuts.
-- Press Alt to reveal Windows' hidden underlines. Shortcut capture still records Alt combinations; press Tab to leave the capture field before using form access keys. Captions and access keys currently use English letters.
+- Added **Clear history… / Alt+H** directly to the Clipboard history window beside Edit image / Open item.
+- Clearing requires confirmation, with **No** selected by default. It removes all saved entries, including pinned entries and entries hidden by the current search. Cancelling leaves history unchanged.
+- The button follows the existing bottom action row when resizing. Settings retains its existing Clear history action.
+- Clearing saved history does not clear the current Windows clipboard or disable future recording. This release does not change memory management.
 
 ## Validation
-91 sync/protocol/conflict checks, 423 native regressions, 513 input/UI checks (including Windows Alt+K dispatch and checkbox toggling), shared wheel handling, screenshot editor and PNG save regressions, notification registration, 48 updater checks and updater progress checks.
+The final build passed isolated checks for the new button, cancellation, confirmed deletion of pinned/search-hidden entries and persistence after reloading the history store. 48 updater regression checks passed; all executable versions and release-manifest hashes were verified. The full desktop-interaction suite was not rerun for this focused patch.
 
-## Limitations
-OpenBao synchronization is experimental and requires a reachable HTTPS server with a trusted certificate, KV v2 and a provisioned userpass account/policy. It does not provide account registration, MFA login, non-root namespaces or reverse-proxy URL prefixes. Ordered layout/language lists are resolved as whole settings. Deletion records are retained without expiry. Missing keyboard layouts block applying a profile. Download/Upload replace a whole profile and are intended for initial setup or deliberate recovery; use Resolve individual conflicts for normal conflicts. Existing browser-selection and clipboard/accessibility limitations remain unchanged.
+## Known limitations
+Existing asynchronous-editor selection/clipboard limitations remain; this release does not fix the reported ChatGPT selection mismatch. Dictionary typo correction and OpenBao synchronization remain experimental as documented in v0.6.28.
 
 **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 contains all three executables, a release manifest, offline dictionaries, documentation and license notices. It contains no personal settings, passwords, server address, clipboard history, Tesseract installation or language models.
+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.
 
 Build and package:
 
@@ -26,4 +26,4 @@ Build and package:
 .\package.ps1 -PublishRelease
 ```
 
-Commit the archive, checksum and sources together. Publish both assets on a stable `release-vX.Y.Z` tag 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 @@
-e6597d11fc388979e972c8572e2471a00dec6c3782414a22d396072508fe7329  KSwitcher-win-x64.zip
+c9c3e3579575a41d434201d4f37bf3829e53c1ef23c42cb1c077930dfe8fdfa6  KSwitcher-win-x64.zip

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 0,6,27,0
- PRODUCTVERSION 0,6,27,0
+ FILEVERSION 0,6,29,0
+ PRODUCTVERSION 0,6,29,0
  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", "0.6.27"
+   VALUE "FileVersion", "0.6.29"
   END
  END
  BLOCK "VarFileInfo"

src/app.cpp

@@ -73,6 +73,8 @@ class Transaction
     Clip snapshot;
     DWORD expected{};
     bool captured{};
+    mutable bool invalidLogged{};
+    unsigned copyNumber{};
     std::wstring adopted;
 
   public:
@@ -108,8 +110,18 @@ class Transaction
     }
     bool valid() const
     {
-        return target && IsWindow(target) && GetForegroundWindow() == target &&
-               app.inputVersion.load() == version;
+        auto foreground = GetForegroundWindow();
+        auto currentVersion = app.inputVersion.load();
+        bool ok = target && IsWindow(target) && foreground == target && currentVersion == version;
+        if (!ok && !invalidLogged)
+        {
+            invalidLogged = true;
+            diagnosticEvent(L"Context invalid: target=" + std::to_wstring((uintptr_t)target) +
+                L" alive=" + std::to_wstring(IsWindow(target)) + L" foreground=" +
+                std::to_wstring((uintptr_t)foreground) + L" expectedVersion=" + std::to_wstring(version) +
+                L" currentVersion=" + std::to_wstring(currentVersion));
+        }
+        return ok;
     }
     void check()
     {
@@ -144,10 +156,14 @@ class Transaction
     }
     std::wstring copy()
     {
+        const auto started = GetTickCount64();
+        const auto number = ++copyNumber;
         if (!valid())
             return {};
         write(textClip(L"\x2063KSwitcher-" + std::to_wstring(GetTickCount64())));
         DWORD before = expected;
+        diagnosticEvent(L"Copy begin number=" + std::to_wstring(number) + L" sentinelSequence=" +
+            std::to_wstring(before) + L" target=" + std::to_wstring((uintptr_t)target));
         if (!valid() || !chord(L'C', MOD_CONTROL))
         {
             diagnosticEvent(L"Copy failed: context changed or simulated Ctrl+C blocked");
@@ -166,6 +182,10 @@ class Transaction
             DWORD now = GetClipboardSequenceNumber();
             if (now != changed)
             {
+                diagnosticEvent(L"Copy sequence number=" + std::to_wstring(number) + L" from=" +
+                    std::to_wstring(changed) + L" to=" + std::to_wstring(now) + L" elapsedMs=" +
+                    std::to_wstring(GetTickCount64() - started) + L" owner=" +
+                    std::to_wstring((uintptr_t)GetClipboardOwner()));
                 changedAgain |= changed != before;
                 changed = now;
                 stable = GetTickCount64();
@@ -183,7 +203,8 @@ class Transaction
                     return {};
                 if (!chord(L'C', MOD_CONTROL))
                     return {};
-                diagnosticEvent(L"Copy retry: clipboard unchanged after Ctrl+C");
+                diagnosticEvent(L"Copy retry: clipboard unchanged after Ctrl+C number=" + std::to_wstring(number) +
+                    L" attempt=" + std::to_wstring(attempts + 1) + L" elapsedMs=" + std::to_wstring(GetTickCount64() - started));
                 ++attempts;
                 retryAt = GetTickCount64() + 250;
             }
@@ -191,6 +212,10 @@ class Transaction
         }
         if (changed == before || !valid())
         {
+            diagnosticEvent(L"Copy end number=" + std::to_wstring(number) + L" attempts=" +
+                std::to_wstring(attempts) + L" elapsedMs=" + std::to_wstring(GetTickCount64() - started) +
+                L" sequence=" + std::to_wstring(GetClipboardSequenceNumber()) + L" clipboardOpenBy=" +
+                std::to_wstring((uintptr_t)GetOpenClipboardWindow()));
             diagnosticEvent(changed == before ? L"Copy failed: clipboard timeout (2000 ms)" :
                                     L"Copy failed: context changed");
             return {};
@@ -201,6 +226,9 @@ class Transaction
         expected = changed;
         auto clip = readClipboard(app.window);
         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) +
+            L" text=" + diagnosticText(text));
         adopted = text;
         check();
         for (auto &f : clip.formats)
@@ -233,6 +261,27 @@ class Transaction
                            const std::function<bool(const std::wstring &)> &suffixMatches = {})
     {
         // WebView word boundaries are only candidates; exact verification is mandatory.
+        diagnosticEvent(L"Selection begin steps=" + std::to_wstring(count) + L" expected=" + diagnosticText(wordCandidate));
+        GUITHREADINFO gui{sizeof(gui)};
+        if (GetGUIThreadInfo(GetWindowThreadProcessId(target, nullptr), &gui))
+        {
+            wchar_t cls[128]{};
+            GetClassNameW(gui.hwndFocus, cls, 128);
+            std::wstring offsets = L"unavailable";
+            if (_wcsicmp(cls, L"Edit") == 0)
+            {
+                DWORD_PTR range{};
+                if (SendMessageTimeoutW(gui.hwndFocus, EM_GETSEL, 0, 0,
+                                       SMTO_ABORTIFHUNG | SMTO_BLOCK, 25, &range) && (DWORD)range != 0xffffffff)
+                    offsets = std::to_wstring(LOWORD(range)) + L"," + std::to_wstring(HIWORD(range));
+            }
+            diagnosticEvent(L"Selection editor class=" + std::wstring(cls) + L" focus=" +
+                std::to_wstring((uintptr_t)gui.hwndFocus) + L" caretWindow=" + std::to_wstring((uintptr_t)gui.hwndCaret) +
+                L" caretRect=" + std::to_wstring(gui.rcCaret.left) + L"," + std::to_wstring(gui.rcCaret.top) +
+                L"," + std::to_wstring(gui.rcCaret.right) + L"," + std::to_wstring(gui.rcCaret.bottom) +
+                L" layout=" + std::to_wstring((uintptr_t)windowLayout(target)) + L" selectionOffsets=" + offsets);
+        }
+        else diagnosticEvent(L"Selection editor: focus/caret/selection unavailable");
         if (needsSelectionDelay(target) && !wordCandidate.empty() &&
             std::all_of(wordCandidate.begin(), wordCandidate.end(),
                         [](wchar_t c) { return letter(c) || iswdigit(c); }))
@@ -241,6 +290,7 @@ class Transaction
                 return {};
             Sleep(25);
             auto text = copy();
+            diagnosticEvent(L"Selection word-boundary match=" + std::to_wstring(matches(text)) + L" copied=" + diagnosticText(text));
             if (valid() && matches(text))
             {
                 diagnosticEvent(L"Selection: verified word boundary");
@@ -251,6 +301,7 @@ class Transaction
             Sleep(25);
         }
         auto text = select(count) ? copy() : std::wstring{};
+        diagnosticEvent(L"Selection initial match=" + std::to_wstring(matches(text)) + L" copied=" + diagnosticText(text));
         // Chromium editors can apply only part of a burst of Shift+Left events.
         // Extend only a verified suffix; never replace a partial or unrelated range.
         if (valid() && !matches(text) && !text.empty() &&
@@ -263,10 +314,11 @@ class Transaction
             {
                 if (!valid() || !chord(VK_LEFT, MOD_SHIFT))
                     return {};
+                diagnosticEvent(L"Selection recovery Shift+Left sent=" + std::to_wstring(i + 1) + L" total=" + std::to_wstring(missing));
                 Sleep(25);
             }
             text = copy();
-            diagnosticEvent(L"Selection: suffix recovery match=" + std::to_wstring(matches(text)));
+            diagnosticEvent(L"Selection: suffix recovery match=" + std::to_wstring(matches(text)) + L" copied=" + diagnosticText(text));
         }
         return text;
     }
@@ -532,6 +584,7 @@ void App::applySettings(const Settings &requested)
         run.reset();
         last.reset();
         ++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.
     enqueue([this] { autoCorrector.configure({}, {}); });
@@ -560,6 +613,7 @@ void App::reloadLayouts()
         run.reset();
         last.reset();
         ++inputVersion;
+        if (busy) diagnosticEvent(L"Input context changed: layouts reloaded version=" + std::to_wstring(inputVersion.load()));
     }
     registerHotkeys(settings);
 }
@@ -589,6 +643,7 @@ void App::resetInput()
 {
     std::lock_guard lock(stateMutex);
     ++inputVersion;
+    if (busy) diagnosticEvent(L"Input context changed: reset version=" + std::to_wstring(inputVersion.load()));
     run.reset();
     last.reset();
 }
@@ -606,6 +661,9 @@ void App::keyboard(const KBDLLHOOKSTRUCT &k, UINT mods)
     if (isHotkey(vk, mods))
         return;
     ++inputVersion;
+    if (busy) diagnosticEvent(L"Input context changed: keyboard vk=" + std::to_wstring(vk) +
+        L" modifiers=" + std::to_wstring(mods) + L" injected=" + std::to_wstring((k.flags & LLKHF_INJECTED) != 0) +
+        L" version=" + std::to_wstring(inputVersion.load()));
     last.reset();
     HWND fg = GetForegroundWindow();
     HKL layout = windowLayout(fg);
@@ -839,8 +897,11 @@ LRESULT CALLBACK App::mouseProc(int code, WPARAM wp, LPARAM lp)
         // KSwitcher generates no mouse input. Remote clicks invalidate a typing
         // range just like local clicks, including while a transaction is pending.
         if (wp == WM_LBUTTONDOWN || wp == WM_RBUTTONDOWN || wp == WM_MBUTTONDOWN || wp == WM_MOUSEWHEEL)
+        {
+            if (current->busy) diagnosticEvent(L"Input context changed: mouse message=" + std::to_wstring(wp));
             current->resetInput();
         }
+    }
     return CallNextHookEx(nullptr, code, wp, lp);
 }
 void App::dispatch(int command)
@@ -1010,9 +1071,10 @@ void App::transform(int command, int snippet)
                                     !(command == 0 && reason == L"paste-sent-unverified")},
                                 {"elapsedMs", GetTickCount64() - start}, {"foregroundSame", GetForegroundWindow() == target},
                                 {"inputSame", app.inputVersion.load() == version}, {"original", bounded(text)},
-                                {"expected", bounded(result)}, {"actual", bounded(actual)},
-                                {"originalUnits", text.size()}, {"expectedUnits", result.size()}, {"actualUnits", actual.size()},
-                                {"textTruncated", text.size() > 4096 || result.size() > 4096 || actual.size() > 4096}};
+                                {"expected", bounded(verification == L"selection-mismatch" ? expected : result)}, {"actual", bounded(actual)},
+                                {"selectionExpected", bounded(expected)},
+                                {"originalUnits", text.size()}, {"expectedUnits", (verification == L"selection-mismatch" ? expected : result).size()}, {"actualUnits", actual.size()},
+                                {"textTruncated", text.size() > 4096 || result.size() > 4096 || actual.size() > 4096 || expected.size() > 4096}};
                             diagnosticOperation(record.dump(-1, ' ', true, DiagnosticJson::error_handler_t::replace));
                         }
                         catch (...) {} // Logging must never abort a completed input transaction.
@@ -1135,6 +1197,8 @@ void App::transform(int command, int snippet)
                     if (newlines(text) != newlines(previous->result))
                     {
                         reason = L"undo-verification-mismatch";
+                        actual = text;
+                        verification = L"selection-mismatch";
                         if (tx.valid())
                             chord(VK_RIGHT);
                         return;
@@ -1177,6 +1241,8 @@ void App::transform(int command, int snippet)
                         std::to_wstring(recent.keys.size()) + L" match=" + std::to_wstring(hint));
                     if (hint < 0)
                     {
+                        actual = text;
+                        verification = L"selection-mismatch";
                         reason = text.empty() ? L"recent-copy-empty" : L"recent-verification-mismatch";
                         if (tx.valid())
                             chord(VK_RIGHT);
@@ -1194,6 +1260,8 @@ void App::transform(int command, int snippet)
                                         { return newlines(candidate) == newlines(previous->result); });
                     if (newlines(text) != newlines(previous->result))
                     {
+                        actual = text;
+                        verification = L"selection-mismatch";
                         reason = L"previous-result-verification-mismatch";
                         if (tx.valid())
                             chord(VK_RIGHT);

src/app_sync.inl

@@ -35,7 +35,10 @@ std::wstring App::syncCommand(int action, const std::vector<SyncChoice> &choices
                 auto base = action == 1 || action == 4 ? loadSyncBase(data, c) : Bytes{};
                 result = synchronize(*provider, base, sharedSyncSettings(snapshot),
                     action == 2 ? SyncAction::Download : action == 3 ? SyncAction::Upload : SyncAction::Automatic,
-                    [&](const Bytes &b) { restoreSyncSettings(b, snapshot, availableLayouts); }, choices);
+                    [&](const Bytes &b) { restoreSyncSettings(b, snapshot, availableLayouts, c.keepLocalLayouts); }, choices,
+                    c.keepLocalLayouts);
+                if (result.success && c.keepLocalLayouts)
+                    result.status += L" Partial sync: this PC's layouts and their shortcuts were kept; server layouts were preserved.";
             }
             catch (const nlohmann::json::exception &) { result.status = L"Invalid sync data or server response."; }
             catch (const std::exception &e) { result.status = wide(e.what()); }
@@ -65,7 +68,7 @@ void App::pollSync()
                     nextSync = GetTickCount64() + 2000;
                     return;
                 }
-                auto next = restoreSyncSettings(syncResult.settings, settings, layouts);
+                auto next = restoreSyncSettings(syncResult.settings, settings, layouts, syncConnection.keepLocalLayouts);
                 if (encodeSettings(next) != syncSnapshot)
                 {
                     atomicWrite(data / L"settings-before-sync.bin", protect(syncSnapshot));

src/autocorrect.cpp

@@ -164,6 +164,24 @@ std::optional<AutoSuggestion> AutoCorrector::suggest(const std::wstring &typed,
     auto sourceLanguage = layoutLanguage(layouts[source]);
     if (!dictionaries.contains(sourceLanguage))
         return {};
+    const std::wstring alphabet = sourceLanguage == L"en" ? L"abcdefghijklmnopqrstuvwxyz" :
+        sourceLanguage == L"uk" ? L"абвгґдеєжзиіїйклмнопрстуфхцчшщьюя" : L"абвгдеёжзийклмнопрстуфхцчшщъыьэюя";
+    auto small = lower(word);
+    bool sameLanguage = safeAutoWord(word, settings.autoMinLength) &&
+        small.find_first_not_of(alphabet) == small.npos &&
+        std::find(settings.cycle.begin(), settings.cycle.end(), layouts[source].id) != settings.cycle.end();
+    auto sameLayout = [&](std::wstring text)
+    {
+        if (word != small) text[0] = upper(text.substr(0, 1))[0];
+        return AutoSuggestion{source, source, prefix + text + suffix};
+    };
+    if (settings.autoReplace && sameLanguage)
+    {
+        auto replacement = settings.autoReplacements.find(small);
+        if (replacement != settings.autoReplacements.end() &&
+            replacement->second.find_first_not_of(alphabet) == small.npos)
+            return sameLayout(replacement->second);
+    }
     auto personal = [&](const std::wstring &language, const std::wstring &candidate)
     {
         auto found = settings.autoWords.find(language);
@@ -203,7 +221,54 @@ std::optional<AutoSuggestion> AutoCorrector::suggest(const std::wstring &typed,
             (!candidate || priority(i) < priority(candidate->target)))
             candidate = AutoSuggestion{source, i, prefix + converted + suffix};
     }
+    if (candidate || matchedText || !settings.autoTypos || !sameLanguage || word.size() < 4)
         return candidate;
+    // Generate only single edits. Stop at a second distinct dictionary hit,
+    // including rare hits: frequency limits must never hide ambiguity.
+    std::wstring found;
+    int foundRank = 0;
+    std::set<std::wstring> personalTargets;
+    if (auto it = settings.autoWords.find(sourceLanguage); it != settings.autoWords.end())
+        for (const auto &text : it->second) personalTargets.insert(lower(text));
+    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);
+        if (!rank) return true;
+        if (!found.empty()) return false;
+        found = text;
+        foundRank = rank;
+        return true;
+    };
+    for (size_t i = 0; i < small.size(); ++i)
+    {
+        auto text = small;
+        text.erase(i, 1);
+        if (!consider(text)) return {};
+        if (i + 1 < small.size())
+        {
+            text = small;
+            std::swap(text[i], text[i + 1]);
+            if (!consider(text)) return {};
+        }
+        for (wchar_t c : alphabet)
+        {
+            text = small;
+            text[i] = c;
+            if (!consider(text)) return {};
+        }
+    }
+    if (small.size() < 32)
+        for (size_t i = 0; i <= small.size(); ++i)
+            for (wchar_t c : alphabet)
+            {
+                auto text = small;
+                text.insert(i, 1, c);
+                if (!consider(text)) return {};
+            }
+    if (!found.empty() && (settings.autoMaxRank == 0 || foundRank <= settings.autoMaxRank))
+        return sameLayout(found);
+    return {};
 }
 int matchAutoInput(const Run &run, const std::wstring &text, const std::vector<Layout> &layouts,
                    const Layout &physical, const Settings &settings)

src/core.h

@@ -54,6 +54,8 @@ struct Settings
     bool recent = true, switchLayout = true, history = true, autostart = false, awake = false;
     bool elevatedAutostart = false;
     bool autoCorrect = false;
+    bool autoReplace = false, autoTypos = false;
+    std::map<std::wstring, std::wstring> autoReplacements;
     bool writeLog = true;
     bool screenshotAutoOpenEditor = false;
     bool useTesseract = false;

src/diagnostics.h

@@ -37,7 +37,8 @@ inline std::vector<OperationLogRow> parseOperationLog(const std::wstring &conten
                     L"Operation: " + field("attempt") + L"\r\nResult: " + row.outcome +
                     L"\r\nVerification: " + field("verification") + L"\r\nElapsed: " +
                     std::to_wstring(j.value("elapsedMs", 0ULL)) + L" ms\r\n\r\nOriginal:\r\n" +
-                    field("original") + L"\r\n\r\nExpected result:\r\n" + field("expected") +
+                    field("original") + L"\r\n\r\nExpected selection:\r\n" + field("selectionExpected") +
+                    L"\r\n\r\nExpected result / verification target:\r\n" + field("expected") +
                     L"\r\n\r\nRead back:\r\n" + field("actual") + L"\r\n\r\nForeground unchanged: " +
                     (j.value("foregroundSame", false) ? L"yes" : L"no") + L"\r\nInput context unchanged: " +
                     (j.value("inputSame", false) ? L"yes" : L"no") + L"\r\nText truncated: " +

src/platform.cpp

@@ -407,12 +407,16 @@ bool selectPrevious(size_t count, const std::function<bool()> &valid)
     // Shift+Left events can all use the same caret position and select only one
     // character. Give each change time to settle before sending the next one.
     const auto target = GetForegroundWindow();
+    diagnosticEvent(L"SelectPrevious requested=" + std::to_wstring(count) +
+        L" mode=" + (needsSelectionDelay(target) ? std::wstring(L"paced-25ms") : std::wstring(L"batch")));
     if (needsSelectionDelay(target))
     {
         for (size_t i = 0; i < count; ++i)
         {
             if (!valid() || GetForegroundWindow() != target || !chord(VK_LEFT, MOD_SHIFT))
                 return false;
+            if (i < 32 || i + 1 == count)
+                diagnosticEvent(L"SelectPrevious Shift+Left sent=" + std::to_wstring(i + 1));
             Sleep(25);
         }
         return valid() && GetForegroundWindow() == target;
@@ -434,7 +438,10 @@ bool selectPrevious(size_t count, const std::function<bool()> &valid)
             add(VK_LEFT, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP);
         }
         add(VK_SHIFT, KEYEVENTF_KEYUP);
-        if (SendInput((UINT)inputs.size(), inputs.data(), sizeof(INPUT)) != inputs.size())
+        auto sent = SendInput((UINT)inputs.size(), inputs.data(), sizeof(INPUT));
+        diagnosticEvent(L"SelectPrevious batch offset=" + std::to_wstring(offset) + L" eventsRequested=" +
+            std::to_wstring(inputs.size()) + L" eventsSent=" + std::to_wstring(sent));
+        if (sent != inputs.size())
             return false;
     }
     return valid();
@@ -574,7 +581,7 @@ DiagnosticBuffer diagnosticBuffer;
 }
 std::wstring DiagnosticBuffer::record(const std::wstring &message, bool problem, ULONGLONG now)
 {
-    while (!entries.empty() && (entries.size() >= 40 || now - entries.front().first > 30000))
+    while (!entries.empty() && (entries.size() >= 128 || now - entries.front().first > 30000))
         entries.pop_front();
     entries.emplace_back(now, message);
     if (!problem)

src/storage.cpp

@@ -108,6 +108,19 @@ void validateSettings(const Settings &s)
             throw std::runtime_error("Unsupported auto-correction language");
     if (s.autoNever.size() > 10000 || s.autoExcluded.size() > 1000)
         throw std::runtime_error("Too many auto-correction exceptions");
+    if (s.autoReplacements.size() > 10000)
+        throw std::runtime_error("Too many automatic replacements");
+    for (const auto &[from, to] : s.autoReplacements)
+    {
+        bool valid = false;
+        for (auto alphabet : {L"abcdefghijklmnopqrstuvwxyz", L"абвгґдеєжзиіїйклмнопрстуфхцчшщьюя",
+                              L"абвгдеёжзийклмнопрстуфхцчшщъыьэюя"})
+            valid |= !from.empty() && !to.empty() && from.size() <= 32 && to.size() <= 32 &&
+                     from == lower(from) && to == lower(to) && from != to &&
+                     from.find_first_not_of(alphabet) == from.npos && to.find_first_not_of(alphabet) == to.npos;
+        if (!valid)
+            throw std::runtime_error("Replacement pairs must be different lowercase words of 1-32 letters in the same language");
+    }
     for (const auto &[language, words] : s.autoWords)
     {
         std::wstring alphabet = language == L"en" ? L"abcdefghijklmnopqrstuvwxyz" :
@@ -172,6 +185,15 @@ Settings decodeSettings(const Bytes &bytes, const std::vector<Layout> &layouts)
     s.elevatedAutostart = j.value("autostartAsAdministrator", false);
     s.awake = j.value("preventScreenLock", false);
     s.autoCorrect = j.value("autoCorrectLayout", false);
+    s.autoReplace = j.value("autoCorrectReplace", false);
+    s.autoTypos = j.value("autoCorrectTypos", false);
+    if (j.contains("autoCorrectReplacements"))
+        for (auto &[from, to] : j.at("autoCorrectReplacements").items())
+        {
+            auto key = lower(wide(from));
+            if (!s.autoReplacements.emplace(key, lower(wide(to.get<std::string>()))).second)
+                throw std::runtime_error("Duplicate automatic replacement");
+        }
     s.autoMaxRank = j.value("autoCorrectMaxRank", 0);
     s.autoMinLength = j.value("autoCorrectMinLength", 3);
     s.autoPrefixChars = str(j, "autoCorrectPrefixChars", s.autoPrefixChars);
@@ -268,6 +290,11 @@ Bytes encodeSettings(const Settings &s)
     for (auto &id : s.cycle)
         j["layouts"].push_back(utf8(id));
     j["autoCorrectLayout"] = s.autoCorrect;
+    j["autoCorrectReplace"] = s.autoReplace;
+    j["autoCorrectTypos"] = s.autoTypos;
+    j["autoCorrectReplacements"] = Json::object();
+    for (const auto &[from, to] : s.autoReplacements)
+        j["autoCorrectReplacements"][utf8(from)] = utf8(to);
     j["autoCorrectMaxRank"] = s.autoMaxRank;
     j["autoCorrectMinLength"] = s.autoMinLength;
     j["autoCorrectPrefixChars"] = utf8(s.autoPrefixChars);

src/sync.cpp

@@ -17,7 +17,7 @@ Json configJson(const SyncConfig &c)
 {
     return {{"enabled", c.enabled}, {"provider", utf8(c.provider)}, {"server", utf8(c.server)},
         {"mount", utf8(c.mount)}, {"path", utf8(c.path)}, {"authMount", utf8(c.authMount)},
-        {"username", utf8(c.username)}};
+        {"username", utf8(c.username)}, {"keepLocalLayouts", c.keepLocalLayouts}};
 }
 std::wstring credentialName(const SyncConfig &c)
 {
@@ -154,6 +154,7 @@ SyncConfig loadSyncConfig(const std::filesystem::path &root)
     if (!syncVisible(root)) return c;
     auto j = parse(readFile(root / L"sync.json", 16384));
     c.enabled = j.value("enabled", false);
+    c.keepLocalLayouts = j.value("keepLocalLayouts", false);
     c.provider = wide(j.value("provider", "openbao"));
     c.server = wide(j.value("server", ""));
     c.mount = wide(j.value("mount", "kswitcher"));
@@ -221,30 +222,50 @@ Bytes sharedSyncSettings(const Settings &s)
         "historyEnabled", "maxItems", "maxTotalMegabytes", "maxImageMegabytes", "writeLog", "preventScreenLock"}) j.erase(key);
     return bytes(canonicalProfile(j));
 }
-Settings restoreSyncSettings(const Bytes &shared, const Settings &local, const std::vector<Layout> &layouts)
+Settings restoreSyncSettings(const Bytes &shared, const Settings &local, const std::vector<Layout> &layouts, bool keepLocalLayouts)
 {
     auto j = parse(shared), original = parse(encodeSettings(local));
     if (!j.contains("snippetTombstones")) j["snippetTombstones"] = Json::array();
+    if (!j.contains("autoCorrectReplace")) j["autoCorrectReplace"] = false;
+    if (!j.contains("autoCorrectTypos")) j["autoCorrectTypos"] = false;
+    if (!j.contains("autoCorrectReplacements")) j["autoCorrectReplacements"] = Json::object();
     auto allowed = parse(sharedSyncSettings(local));
     if (!j.is_object() || j.value("format", "") != "kswitcher-settings" || j.value("schemaVersion", 0) != 1)
         throw std::runtime_error("Unsupported synchronized settings format.");
     for (auto it = j.begin(); it != j.end(); ++it)
         if (!allowed.contains(it.key())) throw std::runtime_error("Remote profile contains unsupported or local-only fields.");
     if (j.size() != allowed.size()) throw std::runtime_error("Remote profile is incomplete.");
-    // decodeSettings intentionally ignores hotkeys for missing layouts during import.
-    // Sync must stop instead, otherwise the next upload would lose those bindings.
     std::set<std::string> installed;
     for (const auto &layout : layouts) installed.insert(utf8(layout.id));
+    std::set<std::string> missing;
     for (const auto &id : j.at("layouts"))
-        if (!installed.contains(id.get<std::string>())) throw std::runtime_error("Install the remote profile's keyboard layouts before syncing.");
+        if (!installed.contains(id.get<std::string>())) missing.insert(id.get<std::string>());
     for (const auto &key : j.at("layoutHotkeys"))
-        if (!installed.contains(key.at("layoutId").get<std::string>())) throw std::runtime_error("Install the remote profile's keyboard layouts before syncing.");
+        if (!installed.contains(key.at("layoutId").get<std::string>())) missing.insert(key.at("layoutId").get<std::string>());
+    if (!keepLocalLayouts && !missing.empty())
+    {
+        std::wstring message = L"Missing keyboard layouts on this PC: ";
+        for (const auto &id : missing)
+        {
+            auto code = id.starts_with("win:") ? id.substr(4) : id;
+            wchar_t language[128]{};
+            if (code.size() == 8 && code.find_first_not_of("0123456789abcdefABCDEF") == code.npos)
+                GetLocaleInfoW(MAKELCID(LOWORD(std::stoul(code, nullptr, 16)), SORT_DEFAULT), LOCALE_SENGLISHLANGUAGENAME,
+                               language, 128);
+            if (message.back() != L' ') message += L"; ";
+            message += (language[0] ? std::wstring(language) : L"Unknown layout") + L" [" + wide(id) + L"]";
+        }
+        message += L". Install these exact layouts, or enable 'Keep this PC's layouts' below and sync other settings.";
+        throw std::runtime_error(utf8(message));
+    }
+    if (keepLocalLayouts)
+        for (auto key : {"layouts", "layoutHotkeys"}) j[key] = original.at(key);
     original.update(j);
     return decodeSettings(bytes(original), layouts);
 }
 #include "sync_merge.inl"
 SyncResult synchronize(SyncProvider &provider, const Bytes &base, const Bytes &local, SyncAction action,
-    const std::function<void(const Bytes &)> &validate, const std::vector<SyncChoice> &choices)
+    const std::function<void(const Bytes &)> &validate, const std::vector<SyncChoice> &choices, bool keepLocalLayouts)
 {
     if (local.size() > Limit) throw std::runtime_error("Settings exceed the sync size limit.");
     if (validate) validate(local);
@@ -255,11 +276,25 @@ SyncResult synchronize(SyncProvider &provider, const Bytes &base, const Bytes &l
         return {true, local, provider.write(local, 0), L"Uploaded new profile."};
     }
     if (validate && action != SyncAction::Upload) validate(remote.settings);
+    auto mergeLocal = local, mergeBase = base;
+    if (keepLocalLayouts)
+    {
+        // Never upload a locally filtered projection over another PC's layout setup.
+        const auto remoteJson = parse(remote.settings);
+        auto preserve = [&](const Bytes &profile)
+        {
+            auto j = parse(profile);
+            for (auto key : {"layouts", "layoutHotkeys"}) j[key] = remoteJson.at(key);
+            return bytes(j);
+        };
+        mergeLocal = preserve(local);
+        if (!base.empty()) mergeBase = preserve(base);
+    }
     SyncMerge merged;
-    if (action == SyncAction::Automatic) merged = mergeSyncProfile(base, local, remote.settings, choices);
+    if (action == SyncAction::Automatic) merged = mergeSyncProfile(mergeBase, mergeLocal, remote.settings, choices);
     else
     {
-        auto selected = bytes(normalizeProfile(parse(action == SyncAction::Download ? remote.settings : local)));
+        auto selected = bytes(normalizeProfile(parse(action == SyncAction::Download ? remote.settings : mergeLocal)));
         merged = {selected, selected, selected, {}};
     }
     if (validate) { validate(merged.local); validate(merged.remote); }
@@ -308,7 +343,9 @@ Bytes loadSyncBase(const std::filesystem::path &root, const SyncConfig &c)
     auto path = root / L"sync-base.bin";
     if (!std::filesystem::exists(path)) return {};
     auto j = parse(unprotect(readFile(path, Limit + 65536)));
-    return j.at("connection") == configJson(c) ? bytes(j.at("settings")) : Bytes{};
+    auto connection = j.at("connection");
+    if (!connection.contains("keepLocalLayouts")) connection["keepLocalLayouts"] = false;
+    return connection == configJson(c) ? bytes(j.at("settings")) : Bytes{};
 }
 void saveSyncBase(const std::filesystem::path &root, const SyncConfig &c, const Bytes &base)
 {

src/sync.h

@@ -7,6 +7,7 @@ namespace ks
 struct SyncConfig
 {
     bool enabled{};
+    bool keepLocalLayouts{};
     std::wstring provider = L"openbao", server, mount = L"kswitcher",
         path = L"personal/settings", authMount = L"userpass", username;
     bool operator==(const SyncConfig &) const = default;
@@ -52,7 +53,7 @@ SyncMerge mergeSyncProfile(const Bytes &base, const Bytes &local, const Bytes &r
     const std::vector<SyncChoice> &choices = {});
 Bytes mergeSyncSettings(const Bytes &base, const Bytes &local, const Bytes &remote);
 Bytes sharedSyncSettings(const Settings &);
-Settings restoreSyncSettings(const Bytes &, const Settings &, const std::vector<Layout> &);
+Settings restoreSyncSettings(const Bytes &, const Settings &, const std::vector<Layout> &, bool keepLocalLayouts = false);
 enum class SyncAction { Automatic, Download, Upload };
 struct SyncResult
 {
@@ -64,7 +65,8 @@ struct SyncResult
     std::vector<SyncConflict> conflicts;
 };
 SyncResult synchronize(SyncProvider &, const Bytes &base, const Bytes &local, SyncAction,
-    const std::function<void(const Bytes &)> &validate = {}, const std::vector<SyncChoice> &choices = {});
+    const std::function<void(const Bytes &)> &validate = {}, const std::vector<SyncChoice> &choices = {},
+    bool keepLocalLayouts = false);
 Bytes loadSyncBase(const std::filesystem::path &, const SyncConfig &);
 void saveSyncBase(const std::filesystem::path &, const SyncConfig &, const Bytes &);
 }

src/sync_merge.inl

@@ -4,6 +4,9 @@ namespace
 {
 Json normalizeProfile(Json j)
 {
+    if (!j.contains("autoCorrectReplace")) j["autoCorrectReplace"] = false;
+    if (!j.contains("autoCorrectTypos")) j["autoCorrectTypos"] = false;
+    if (!j.contains("autoCorrectReplacements")) j["autoCorrectReplacements"] = Json::object();
     if (!j.contains("snippetTombstones")) j["snippetTombstones"] = Json::array();
     for (auto &sn : j.at("snippets"))
         if (!sn.contains("id")) sn["id"] = utf8(snippetId({wide(sn.at("trigger").get<std::string>()), L""}));
@@ -46,6 +49,10 @@ Json treeProfile(const Json &source)
 }
 Json flatProfile(Json j)
 {
+    auto &replacements = j["autoCorrectReplacements"];
+    for (auto it = replacements.begin(); it != replacements.end();)
+        if (it.value().is_null()) it = replacements.erase(it);
+        else ++it;
     Json snippets = Json::array(), deleted = Json::array();
     for (const auto &[id, item] : j.at("snippets").items())
     {
@@ -90,6 +97,8 @@ std::wstring fieldLabel(const std::string &key)
         {"convertLastWord", L"Convert recent word"}, {"switchSystemLayout", L"Switch system layout"},
         {"autoCorrectMinLength", L"Minimum word length"}, {"autoCorrectMaxRank", L"Maximum word rank"},
         {"autoCorrectLayout", L"Automatic layout correction"}, {"autoCorrectLanguages", L"Dictionary languages"},
+        {"autoCorrectReplace", L"Custom automatic replacements"}, {"autoCorrectTypos", L"Dictionary typo correction"},
+        {"autoCorrectReplacements", L"Replacement pairs"},
         {"autoCorrectPrefixChars", L"Punctuation before words"}, {"autoCorrectSuffixChars", L"Punctuation after words"},
         {"screenshotAutoOpenEditor", L"Open screenshot editor"}, {"tesseractLanguages", L"OCR languages"},
         {"trigger", L"Trigger"}, {"text", L"Text"}};
@@ -167,8 +176,9 @@ void collisionPaths(const Json &j, std::set<std::string> &paths)
 SyncMerge mergeSyncProfile(const Bytes &base, const Bytes &local, const Bytes &remote, const std::vector<SyncChoice> &choices)
 {
     auto l = treeProfile(parse(local)), r = treeProfile(parse(remote));
-    if (base.empty() && l != r) throw std::runtime_error("First connection: choose Download remote or Upload local.");
-    auto b = base.empty() ? l : treeProfile(parse(base));
+    // With no common history, union independent entries; differing scalar values
+    // remain on their respective devices until the user resolves the conflict.
+    auto b = base.empty() ? Json::object() : treeProfile(parse(base));
     SyncMerge result;
     auto merged = mergeNode(b, l, r, "", L"", choices, result.conflicts, {});
     std::set<std::string> collisions;

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)
@@ -730,6 +730,13 @@ 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)
             {
@@ -1112,6 +1119,25 @@ LRESULT CALLBACK autoOptionsProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             draft.autoExcluded = parseCommaList(value(w, 404));
             draft.autoPrefixChars = value(w, 408);
             draft.autoSuffixChars = value(w, 409);
+            draft.autoReplace = checked(w, 414);
+            draft.autoTypos = checked(w, 415);
+            draft.autoReplacements.clear();
+            std::wistringstream replacements(lower(value(w, 416)));
+            std::wstring line;
+            auto trim = [](std::wstring text)
+            {
+                auto first = text.find_first_not_of(L" \t\r\n");
+                return first == text.npos ? std::wstring{} : text.substr(first, text.find_last_not_of(L" \t\r\n") - first + 1);
+            };
+            while (std::getline(replacements, line))
+            {
+                if (trim(line).empty()) continue;
+                auto equals = line.find(L'=');
+                if (equals == line.npos)
+                    throw std::runtime_error("Enter one replacement per line: typo=correction");
+                if (!draft.autoReplacements.emplace(trim(line.substr(0, equals)), trim(line.substr(equals + 1))).second)
+                    throw std::runtime_error("Each replacement typo must occur only once");
+            }
             if (draft.autoLanguages.size() < 2)
                 throw std::runtime_error("Select at least two languages");
             validateSettings(draft);
@@ -1123,6 +1149,9 @@ LRESULT CALLBACK autoOptionsProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             view->settings->draft.autoMinLength = draft.autoMinLength;
             view->settings->draft.autoPrefixChars = draft.autoPrefixChars;
             view->settings->draft.autoSuffixChars = draft.autoSuffixChars;
+            view->settings->draft.autoReplace = draft.autoReplace;
+            view->settings->draft.autoTypos = draft.autoTypos;
+            view->settings->draft.autoReplacements = std::move(draft.autoReplacements);
             DestroyWindow(w);
         }
         catch (const std::exception &e)
@@ -1153,8 +1182,8 @@ LRESULT CALLBACK autoOptionsProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
 }
 void showAutoOptions(HWND parent, SettingsView *v)
 {
-    HWND w = makeWindow(*v->app, L"KSwitcher.AutoOptions", L"Automatic layout correction", autoOptionsProc,
-                        560, 680);
+    HWND w = makeWindow(*v->app, L"KSwitcher.AutoOptions", L"Automatic correction", autoOptionsProc,
+                        560, 880);
     windowLayoutState(w)->autoOptions = true;
     SetWindowLongPtrW(w, GWLP_HWNDPARENT, (LONG_PTR)parent);
     SetWindowLongPtrW(w, GWLP_USERDATA, (LONG_PTR) new AutoOptionsView{parent, v});
@@ -1192,10 +1221,20 @@ void showAutoOptions(HWND parent, SettingsView *v)
     value(w, 408, v->draft.autoPrefixChars);
     value(w, 409, v->draft.autoSuffixChars);
     label(w, L"Enter punctuation without spaces or separators. These characters are kept.", 18, 530, 525);
-    button(w, L"Open dictionary &folder", 407, 18, 562, 220);
-    label(w, L"After editing files, click OK here, then Save in Settings to reload.", 18, 600, 525);
-    button(w, L"&OK", IDOK, 326, 632, 100);
-    button(w, L"&Cancel", IDCANCEL, 440, 632, 100);
+    checkbox(w, L"Use custom &replacements (take priority over dictionaries)", 414, 18, 562, 524);
+    check(w, 414, v->draft.autoReplace);
+    label(w, L"One pair per line: typo=correction (same language, letters only)", 18, 592, 525);
+    edit(w, 416, 18, 618, 524, 70, ES_MULTILINE | WS_VSCROLL | ES_AUTOVSCROLL | ES_WANTRETURN);
+    std::wstring pairs;
+    for (const auto &[from, to] : v->draft.autoReplacements) pairs += from + L"=" + to + L"\r\n";
+    value(w, 416, pairs);
+    checkbox(w, L"Correct spelling &typos using dictionaries (experimental)", 415, 18, 700, 524);
+    check(w, 415, v->draft.autoTypos);
+    label(w, L"Single edits, 4+ letters; ambiguous words are left unchanged.", 18, 730, 525);
+    button(w, L"Open dictionary &folder", 407, 18, 762, 220);
+    label(w, L"Click OK, then Save in Settings. Enable automatic correction there.", 18, 800, 525);
+    button(w, L"&OK", IDOK, 326, 832, 100);
+    button(w, L"&Cancel", IDCANCEL, 440, 832, 100);
     RECT initial{};
     GetWindowRect(w, &initial);
     initial.right += scale(w, 200);
@@ -1618,6 +1657,7 @@ 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);
     }
@@ -1672,7 +1712,7 @@ void showSettings(App &app, bool visible)
         hotkeyEdit(app, w, 210 + i, 540, 44 + i * 30, 220);
     }
     checkbox(w, L"Open editor after screen capt&ure", 209, 420, 224, 340);
-    checkbox(w, L"Automatically correct layout (e&xperimental)", 207, 18, 210, 395);
+    checkbox(w, L"Automatic correction (e&xperimental)", 207, 18, 210, 395);
     label(w, L"Layout cycle — top to bottom", 18, 240, 400);
     control(w, L"LISTBOX", L"", WS_TABSTOP | WS_VSCROLL | LBS_NOTIFY | LBS_NOINTEGRALHEIGHT | WS_BORDER, 220,
             18, 262, 470, 172);

src/ui_sync.inl

@@ -1,9 +1,29 @@
 #include "ui_sync_conflicts.inl"
 struct SyncView { HWND parent; App *app; };
+void updateSyncControls(HWND w, App &app)
+{
+    bool enabled = checked(w, 601);
+    bool savedEnabled = loadSyncConfig(app.data).enabled;
+    for (int id : {602, 603, 604, 605, 606, 607, 610, 611, 613})
+        EnableWindow(GetDlgItem(w, id), enabled);
+    EnableWindow(GetDlgItem(w, 612), enabled && savedEnabled);
+    EnableWindow(GetDlgItem(w, IDOK), enabled || savedEnabled);
+    value(w, IDOK, enabled ? L"&Save / Sign in / Sync" : L"&Save");
+    std::wstring status;
+    if (!enabled)
+        status = savedEnabled ? L"Click Save to disable synchronization." :
+              L"Synchronization is disabled. Enable it above to configure and sync.";
+    else if (!savedEnabled)
+        status = L"Configure the connection, then click Save / Sign in / Sync to enable synchronization.";
+    else
+        status = app.syncCommand();
+    if (value(w, 608) != status) value(w, 608, status);
+}
 SyncConfig syncFields(HWND w)
 {
     SyncConfig c;
     c.enabled = checked(w, 601);
+    c.keepLocalLayouts = checked(w, 613);
     c.server = value(w, 602);
     while (!c.server.empty() && c.server.back() == L'/') c.server.pop_back();
     c.username = lower(value(w, 603)); c.mount = value(w, 605);
@@ -19,12 +39,19 @@ LRESULT CALLBACK syncProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
     {
         if (msg == WM_TIMER)
         {
-            value(w, 608, v->app->syncCommand());
+            updateSyncControls(w, *v->app);
             return 0;
         }
         if (msg == WM_COMMAND)
         {
             int id = LOWORD(wp);
+            if (id == 601 && HIWORD(wp) == BN_CLICKED)
+            {
+                updateSyncControls(w, *v->app);
+                return 0;
+            }
+            if ((id == IDOK || id == 610 || id == 611 || id == 612) &&
+                !IsWindowEnabled(GetDlgItem(w, id))) return 0;
             if (id == 612) { showSyncConflicts(w, *v->app); return 0; }
             if (id == IDCANCEL) { DestroyWindow(w); return 0; }
             if (id == 609)
@@ -35,18 +62,28 @@ LRESULT CALLBACK syncProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
                 forgetSyncPassword(c);
                 check(w, 601, false);
                 value(w, 604, L"");
+                updateSyncControls(w, *v->app);
                 value(w, 608, L"Disabled. Saved password removed. An in-flight server request may still finish.");
                 KillTimer(w, 1);
                 return 0;
             }
             if (id == IDOK || id == 610 || id == 611)
             {
+                if (!checked(w, 601))
+                {
+                    if (id != IDOK) return 0;
+                    auto c = loadSyncConfig(v->app->data);
+                    c.enabled = false;
+                    saveSyncConfig(v->app->data, c);
+                    value(w, 604, L"");
+                    updateSyncControls(w, *v->app);
+                    return 0;
+                }
                 if (id != IDOK && MessageBoxW(w, id == 610 ?
                     L"Replace this PC's shared settings with the remote profile? A local backup will be saved. Unsaved edits in Settings are not included." :
                     L"Replace the remote profile with this PC's saved settings? OpenBao retains older versions according to its retention policy. Unsaved edits are not included.",
                     L"Resolve synchronization", MB_YESNO | MB_ICONWARNING) != IDYES) return 0;
                 auto c = syncFields(w);
-                if (id != IDOK && !c.enabled) throw std::runtime_error("Enable synchronization first.");
                 if (c.enabled) validateSyncConfig(c);
                 auto password = value(w, 604);
                 try { if (!password.empty()) saveSyncPassword(c, password); }
@@ -55,6 +92,7 @@ LRESULT CALLBACK syncProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
                 value(w, 604, L"");
                 saveSyncConfig(v->app->data, c);
                 value(w, 608, v->app->syncCommand(id == 610 ? 2 : id == 611 ? 3 : 1));
+                updateSyncControls(w, *v->app);
                 SetTimer(w, 1, 1000, nullptr);
                 return 0;
             }
@@ -80,7 +118,7 @@ LRESULT CALLBACK syncProc(HWND w, UINT msg, WPARAM wp, LPARAM lp)
 void showSyncOptions(HWND parent, App &app)
 {
     auto c = loadSyncConfig(app.data);
-    HWND w = makeWindow(app, L"KSwitcher.Sync", L"Settings synchronization - OpenBao", syncProc, 660, 640);
+    HWND w = makeWindow(app, L"KSwitcher.Sync", L"Settings synchronization - OpenBao", syncProc, 660, 672);
     SetWindowLongPtrW(w, GWLP_HWNDPARENT, (LONG_PTR)parent);
     SetWindowLongPtrW(w, GWLP_USERDATA, (LONG_PTR)new SyncView{parent, &app});
     checkbox(w, L"&Enable synchronization with your OpenBao (KV v2)", 601, 18, 18, 620);
@@ -93,15 +131,18 @@ void showSyncOptions(HWND parent, App &app)
     label(w, L"Profile pa&th", 18, 250, 160); edit(w, 606, 190, 246, 450); value(w, 606, c.path);
     label(w, L"&Login mount", 18, 290, 160); edit(w, 607, 190, 286, 450); value(w, 607, c.authMount);
     label(w, L"Sync uses saved settings. Close and reopen Settings after downloading changes.", 18, 330, 622);
-    control(w, L"STATIC", L"", 0, 608, 18, 362, 622, 76);
+    edit(w, 608, 18, 362, 622, 76, ES_MULTILINE | ES_READONLY | WS_VSCROLL | ES_AUTOVSCROLL);
     value(w, 608, app.syncCommand());
-    button(w, L"&Save / Sign in / Sync", IDOK, 18, 452, 200);
-    button(w, L"&Download remote", 610, 230, 452, 195);
-    button(w, L"&Upload local", 611, 437, 452, 203);
-    button(w, L"Resolve &individual conflicts...", 612, 18, 498, 300);
-    label(w, L"Background check: every 10 minutes", 330, 502, 310);
-    button(w, L"Disconnect / &forget password", 609, 18, 550, 290);
-    button(w, L"&Close", IDCANCEL, 540, 550, 100);
+    checkbox(w, L"&Keep this PC's layouts and layout shortcuts (sync other settings)", 613, 18, 446, 622);
+    check(w, 613, c.keepLocalLayouts);
+    button(w, L"&Save / Sign in / Sync", IDOK, 18, 484, 200);
+    button(w, L"&Download remote", 610, 230, 484, 195);
+    button(w, L"&Upload local", 611, 437, 484, 203);
+    button(w, L"Resolve &individual conflicts...", 612, 18, 530, 300);
+    label(w, L"Background check: every 10 minutes", 330, 534, 310);
+    button(w, L"Disconnect / &forget password", 609, 18, 582, 290);
+    button(w, L"&Close", IDCANCEL, 540, 582, 100);
+    updateSyncControls(w, app);
     EnableWindow(parent, FALSE);
     SetTimer(w, 1, 1000, nullptr);
     showRequestedWindow(w); SetForegroundWindow(w);

src/update.h

@@ -2,7 +2,7 @@
 #include "platform.h"
 namespace ks
 {
-inline constexpr wchar_t AppVersion[] = L"0.6.27";
+inline constexpr wchar_t AppVersion[] = L"0.6.29";
 inline constexpr UINT UpdateMessage = WM_APP + 7;
 inline constexpr UINT UpdateCheckIntervalMs = 6 * 60 * 60 * 1000;
 inline constexpr UINT UpdateNotificationRetryMs = 5 * 60 * 1000;

tests/input.cpp

@@ -599,6 +599,9 @@ int main(int argc, char **argv) {
             require(!app.handleKeyboard(f12,true,MOD_CONTROL|MOD_SHIFT),"exact modifiers only");
             app.resetInput();
             app.handleKeyboard(event('A',0x1e),true,0);
+            if (app.run.keys!=L"a" && app.run.keys!=L"A")
+                std::cerr << "Input fixture foreground=" << (uintptr_t)GetForegroundWindow()
+                          << " recorded=" << ks::utf8(app.run.keys) << '\n';
             require(app.run.keys==L"a"||app.run.keys==L"A","external scan recorded with current CapsLock");
             auto keys=app.run.keys; auto version=app.inputVersion.load();
             for(WORD key:{WORD('V'),WORD(VK_SHIFT),WORD(VK_LEFT),WORD(VK_F15),WORD(0xE8)})
@@ -656,6 +659,23 @@ int main(int argc, char **argv) {
             require((GetWindowLongPtrW(GetDlgItem(syncWindow,604),GWL_STYLE)&ES_PASSWORD)!=0,
                     "sync password is masked");
             require(!IsWindowEnabled(app.settingsWindow),"sync dialog owns settings interaction");
+            for(int id:{602,603,604,605,606,607,610,611,612,613,IDOK})
+                require(!IsWindowEnabled(GetDlgItem(syncWindow,id)),"disabled synchronization disables dependent controls");
+            require(IsWindowEnabled(GetDlgItem(syncWindow,601)) && IsWindowEnabled(GetDlgItem(syncWindow,609)) &&
+                    IsWindowEnabled(GetDlgItem(syncWindow,IDCANCEL)),"enable, forget password and close remain available");
+            SendMessageW(syncWindow,WM_COMMAND,612,0);
+            require(!FindWindowW(L"KSwitcher.SyncConflicts",nullptr),"disabled conflict action is ignored");
+            SendDlgItemMessageW(syncWindow,601,BM_SETCHECK,BST_CHECKED,0);
+            SendMessageW(syncWindow,WM_COMMAND,MAKEWPARAM(601,BN_CLICKED),0);
+            for(int id:{602,603,604,605,606,607,610,611,613,IDOK})
+                require(IsWindowEnabled(GetDlgItem(syncWindow,id)),"enabling synchronization immediately enables connection controls");
+            require(!ks::loadSyncConfig(app.data).enabled,"checking enable alone does not connect or persist");
+            auto enabledSync=ks::loadSyncConfig(app.data);
+            enabledSync.enabled=true;
+            enabledSync.server=L"https://sync.example.test";
+            enabledSync.username=L"test";
+            ks::saveSyncConfig(app.data,enabledSync);
+            SendMessageW(syncWindow,WM_COMMAND,MAKEWPARAM(601,BN_CLICKED),0);
             ks::InputRegressionAccess::sampleConflicts(app);
             SendMessageW(syncWindow,WM_COMMAND,612,0);
             auto conflictsWindow=FindWindowW(L"KSwitcher.SyncConflicts",nullptr);
@@ -678,7 +698,7 @@ int main(int argc, char **argv) {
             require(!IsWindowEnabled(syncWindow),"conflict dialog owns sync interaction");
             SendMessageW(conflictsWindow,WM_COMMAND,IDCANCEL,0);
             require(IsWindowEnabled(syncWindow),"closing conflict dialog restores sync window");
-            for(int id:{601,602,603,604,605,606,607,608,609,610,611,612,IDOK,IDCANCEL}) {
+            for(int id:{601,602,603,604,605,606,607,608,609,610,611,612,613,IDOK,IDCANCEL}) {
                 RECT control{},client{};
                 GetWindowRect(GetDlgItem(syncWindow,id),&control);
                 MapWindowPoints(nullptr,syncWindow,reinterpret_cast<POINT*>(&control),2);
@@ -686,8 +706,12 @@ int main(int argc, char **argv) {
                 require(control.left>=0&&control.top>=0&&control.right<=client.right&&control.bottom<=client.bottom,
                         "sync controls fit dialog");
             }
+            SendDlgItemMessageW(syncWindow,601,BM_SETCHECK,BST_UNCHECKED,0);
+            SendMessageW(syncWindow,WM_COMMAND,MAKEWPARAM(601,BN_CLICKED),0);
+            require(IsWindowEnabled(GetDlgItem(syncWindow,IDOK)),"Save remains available to persist disabling sync");
             SendMessageW(syncWindow,WM_COMMAND,IDOK,0);
             require(!ks::loadSyncConfig(app.data).enabled,"saving disabled sync does not enable network access");
+            require(!IsWindowEnabled(GetDlgItem(syncWindow,IDOK)),"Save disables after disabled state is persisted");
             SendMessageW(syncWindow,WM_COMMAND,IDCANCEL,0);
             require(IsWindowEnabled(app.settingsWindow),"closing sync restores parent");
             require(ks::InputRegressionAccess::staleSync(app,false),"in-flight sync cannot overwrite newer local edits");
@@ -704,21 +728,31 @@ int main(int argc, char **argv) {
                 GetWindowRect(autoOptions,&original);
                 // Use a client size above the scrolling baseline at every DPI.
                 UINT dpi=GetDpiForWindow(autoOptions);
-                SetWindowPos(autoOptions,nullptr,0,0,MulDiv(800,dpi,96),MulDiv(900,dpi,96),
+                SetWindowPos(autoOptions,nullptr,0,0,MulDiv(800,dpi,96),MulDiv(1100,dpi,96),
                              SWP_NOMOVE|SWP_NOZORDER|SWP_NOACTIVATE);
                 RECT baseline{}; GetWindowRect(autoOptions,&baseline);
+                RECT clientBefore{}; GetClientRect(autoOptions,&clientBefore);
                 for(int i=0;i<3;++i) GetWindowRect(GetDlgItem(autoOptions,411+i),&before[i]);
                 GetWindowRect(GetDlgItem(autoOptions,IDOK),&buttonBefore);
                 SetWindowPos(autoOptions,nullptr,0,0,baseline.right-baseline.left+240,
                              baseline.bottom-baseline.top+120,SWP_NOMOVE|SWP_NOZORDER|SWP_NOACTIVATE);
+                RECT clientAfter{}; GetClientRect(autoOptions,&clientAfter);
+                // Windows can constrain oversized windows to the current desktop.
+                // Check layout against the actual available client space.
+                int extraBeforeX=std::max(0,int(clientBefore.right)-MulDiv(560,dpi,96));
+                int extraAfterX=std::max(0,int(clientAfter.right)-MulDiv(560,dpi,96));
+                int extraY=std::max(0,int(clientAfter.bottom)-MulDiv(880,dpi,96))-
+                           std::max(0,int(clientBefore.bottom)-MulDiv(880,dpi,96));
                 for(int i=0;i<3;++i) {
                     GetWindowRect(GetDlgItem(autoOptions,411+i),&after[i]);
-                    require(after[i].right-after[i].left==before[i].right-before[i].left+80 &&
-                            after[i].bottom-after[i].top==before[i].bottom-before[i].top+120,
+                    int extraX=(extraAfterX*(i+1)/3-extraAfterX*i/3)-
+                               (extraBeforeX*(i+1)/3-extraBeforeX*i/3);
+                    require(after[i].right-after[i].left==before[i].right-before[i].left+extraX &&
+                            after[i].bottom-after[i].top==before[i].bottom-before[i].top+extraY,
                             "dictionary columns share extra width and receive extra height");
                 }
                 GetWindowRect(GetDlgItem(autoOptions,IDOK),&buttonAfter);
-                require(buttonAfter.left-buttonBefore.left==240 && buttonAfter.top-buttonBefore.top==120,
+                require(buttonAfter.left-buttonBefore.left==extraAfterX-extraBeforeX && buttonAfter.top-buttonBefore.top==extraY,
                         "auto-correction buttons follow bottom-right corner");
                 require(after[0].right<after[1].left && after[1].right<after[2].left &&
                             after[2].bottom<buttonAfter.top,
@@ -735,6 +769,9 @@ int main(int argc, char **argv) {
                         "personal dictionary field fits options window");
             }
             SetDlgItemTextW(autoOptions,412,L"Релізик\r\nрелізик, словечко");
+            SetDlgItemTextW(autoOptions,416,L" Првиіт = Привіт\r\nhelo=hello");
+            SendDlgItemMessageW(autoOptions,414,BM_SETCHECK,BST_CHECKED,0);
+            SendDlgItemMessageW(autoOptions,415,BM_SETCHECK,BST_CHECKED,0);
             SendMessageW(autoOptions,WM_COMMAND,IDOK,0);
             require(!IsWindow(autoOptions),"personal words accepted without file editing");
             SendMessageW(app.settingsWindow,WM_COMMAND,255,0);
@@ -744,6 +781,12 @@ int main(int argc, char **argv) {
             GetDlgItemTextW(autoOptions,412,personalWords,128);
             require(std::wstring(personalWords)==L"релізик, словечко",
                     "personal dictionary normalizes case, newlines and duplicate words");
+            wchar_t pairs[128]{};
+            GetDlgItemTextW(autoOptions,416,pairs,128);
+            require(std::wstring(pairs)==L"helo=hello\r\nпрвиіт=привіт\r\n" &&
+                    SendDlgItemMessageW(autoOptions,414,BM_GETCHECK,0,0)==BST_CHECKED &&
+                    SendDlgItemMessageW(autoOptions,415,BM_GETCHECK,0,0)==BST_CHECKED,
+                    "typo options and normalized replacement pairs survive reopening");
             SendMessageW(autoOptions,WM_COMMAND,IDCANCEL,0);
             if (!app.history) app.history=std::make_unique<ks::History>(temp/L"history-layout");
             ks::showHistory(app,false);

tests/integration.cpp

@@ -23,6 +23,7 @@ HWND host{}, field{};
 ks::Clip saved;
 bool captured = false, failed = false;
 bool conversionOnly = false;
+bool typosOnly = false;
 int pasteBehavior = 0;
 int enterPresses = 0;
 int copyFailuresRemaining = 0, copyRequests = 0;
@@ -427,8 +428,30 @@ LRESULT CALLBACK procedure(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             case 47:
                 require(text() == L"OLDsnipping ", "recent Cyrillic suffix recovery preserves older prefix");
                 require(droppedSelectionKeys == 0, "recent suffix regression dropped four selection keys");
+                app->settings.writeLog = true;
+                prepare(L"prefix wrong ", false);
+                record(L"other ");
+                app->transform(ks::Direct + ru);
+                break;
+            case 48:
+            {
+                auto rows = ks::parseOperationLog(ks::wide(diagnosticLog()));
+                require(text() == L"prefix wrong " && !rows.empty() &&
+                        rows.back().outcome == L"recent-verification-mismatch",
+                        "diagnostic mismatch does not replace unverified text");
+                auto details = rows.back().details;
+                require(details.find(L"selection-mismatch") != details.npos &&
+                        details.find(L"Expected selection:\r\nother ") != details.npos &&
+                        details.find(L"Read back:\r\nwrong ") != details.npos,
+                        "failed verification includes expected and copied text in exported details");
+                require(details.find(L"Copy begin number=") != details.npos &&
+                        details.find(L"Copy result number=") != details.npos &&
+                        details.find(L"Selection initial match=0") != details.npos &&
+                        details.find(L"SelectPrevious") != details.npos,
+                        "incident includes clipboard and selection stages");
                 finish();
                 break;
+            }
             case 30:
             case 32:
             case 34:
@@ -597,6 +620,61 @@ LRESULT CALLBACK procedure(HWND w, UINT msg, WPARAM wp, LPARAM lp)
             }
             case 22:
                 require(text() == L"робить ", "automatic correction selects and converts the whole word across an internal comma");
+                app->settings.autoReplace = true;
+                app->settings.autoReplacements = {{L"helo", L"hello"}};
+                ActivateKeyboardLayout(app->layouts[en].handle, 0);
+                prepare(L"(Helo)! ", false);
+                record(L"(Helo)! ");
+                app->transform(ks::AutoCorrect);
+                break;
+            case 23:
+                require(text() == L"(Hello)! ", "explicit typo pair replaces verified text with punctuation and capital");
+                app->transform(ks::Undo);
+                break;
+            case 24:
+                require(text() == L"(Helo)! ", "Undo restores explicit typo replacement");
+                app->settings.autoReplace = false;
+                app->settings.autoTypos = true;
+                app->settings.autoWords[L"en"].push_back(L"kswitcher");
+                // Use a personal target to avoid bundled dictionary ambiguity.
+                prepare(L"kswithcer ", false);
+                record(L"kswithcer ");
+                app->transform(ks::AutoCorrect);
+                break;
+            case 25:
+                require(text() == L"kswitcher ", "dictionary typo correction replaces text in the current layout");
+                require(ks::readClipboard(app->window).text() == sentinel, "typo correction restores clipboard");
+                app->transform(ks::Undo);
+                break;
+            case 26:
+                require(text() == L"kswithcer ", "Undo restores dictionary typo correction");
+                record(L"kswithcer ");
+                app->transform(ks::AutoCorrect);
+                break;
+            case 27:
+                require(text() == L"kswithcer ", "Undo suppresses the rejected spelling correction");
+                app->settings.autoReplace = true;
+                app->settings.autoReplacements = {{L"tehh", L"the"}};
+                app->autoPredictor.configure(L"dictionaries", app->settings.autoLanguages);
+                prepare(L"", false);
+                {
+                    std::vector<INPUT> inputs;
+                    for (WORD key : std::wstring(L"TEHH X"))
+                        for (DWORD flags : {DWORD(0), DWORD(KEYEVENTF_KEYUP)})
+                        {
+                            auto input = ks::keyboardInput(key == L' ' ? VK_SPACE : key, flags);
+                            input.ki.dwExtraInfo = 123;
+                            inputs.push_back(input);
+                        }
+                    require(SendInput((UINT)inputs.size(), inputs.data(), sizeof(INPUT)) == inputs.size(),
+                            "custom typo and following word submitted without a pause");
+                }
+                break;
+            case 28:
+                require(text() == L"the x", "custom replacement through keyboard hook preserves subsequent typing");
+                app->settings.autoReplace = false;
+                app->settings.autoTypos = false;
+                if (typosOnly) { finish(); break; }
                 stage = 30;
                 break;
             }
@@ -621,6 +699,7 @@ LRESULT CALLBACK procedure(HWND w, UINT msg, WPARAM wp, LPARAM lp)
 int main(int argc, char **argv)
 {
     conversionOnly = argc > 1 && std::string(argv[1]) == "--conversion-only";
+    typosOnly = argc > 1 && std::string(argv[1]) == "--typos-only";
     CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED);
     auto root = std::filesystem::temp_directory_path() /
                 (L"KSwitcher-integration-" + std::to_wstring(GetCurrentProcessId()));
@@ -776,7 +855,7 @@ int main(int argc, char **argv)
                               20, 20, 590, 230, host, nullptr, cls.hInstance, nullptr);
             deadline = GetTickCount64() + 30000;
             SetWindowSubclass(field, observeEnter, 1, 0);
-            if (argc > 1 && std::string(argv[1]) == "--typing-only")
+            if (typosOnly || (argc > 1 && std::string(argv[1]) == "--typing-only"))
                 stage = 20;
             if (argc > 1 && std::string(argv[1]) == "--snippets-only")
                 stage = 30;

tests/sync.cpp

@@ -54,6 +54,10 @@ int main()
         rejects([&] { validateSyncConfig(invalid); }, "reject unsupported provider");
         saveSyncConfig(root, config);
         require(syncVisible(root) && loadSyncConfig(root) == config, "connection round trip");
+        auto partialConfig = config; partialConfig.keepLocalLayouts = true;
+        saveSyncConfig(root, partialConfig);
+        require(loadSyncConfig(root).keepLocalLayouts, "partial sync mode survives restart");
+        saveSyncConfig(root, config);
         auto rawConfig = parse(readFile(root / L"sync.json", 16384));
         require(!rawConfig.contains("password") && !rawConfig.contains("token"), "no secrets in config");
         Settings local;
@@ -84,9 +88,49 @@ int main()
         left = right = j; left["snippets"].push_back({{"trigger", "aaa"}, {"text", "one"}});
         right["snippets"].push_back({{"trigger", "bbb"}, {"text", "two"}});
         require(parse(mergeSyncSettings(base, bytes(left), bytes(right)))["snippets"].size() == 3, "independent snippet additions merge");
-        rejects([&] { mergeSyncSettings({}, bytes(left), base); }, "first sync needs explicit choice");
+        require(parse(mergeSyncSettings({}, bytes(left), base))["snippets"].size() == 2,
+                "first sync merges independent additions without choosing a whole profile");
         require(parse(mergeSyncSettings({}, base, base)) == j, "identical first sync safe");
+        {
+            auto l = j, r = j;
+            l["autoCorrectMinLength"] = 4; r["autoCorrectMinLength"] = 5;
+            l["autoCorrectNever"].push_back("localword");
+            r["autoCorrectNever"].push_back("remoteword");
+            auto plan = mergeSyncProfile({}, bytes(l), bytes(r));
+            require(plan.conflicts.size() == 1 && parse(plan.local)["autoCorrectNever"].size() == 2 &&
+                    parse(plan.remote)["autoCorrectNever"].size() == 2,
+                    "first sync merges lists while preserving scalar conflicts");
+            require(parse(plan.local)["autoCorrectMinLength"] == 4 && parse(plan.remote)["autoCorrectMinLength"] == 5,
+                    "first sync never guesses between different scalar values");
+            auto again = mergeSyncProfile(plan.base, plan.local, plan.remote);
+            require(again.conflicts.size() == 1, "first-sync conflicts survive saving the ancestor");
+            auto resolved = mergeSyncProfile(plan.base, plan.local, plan.remote, {{plan.conflicts[0], false}});
+            require(resolved.conflicts.empty() && parse(resolved.local)["autoCorrectMinLength"] == 5,
+                    "first-sync conflict can be resolved independently");
+        }
         require(SyncIntervalMs == 600000, "background interval is ten minutes");
+        {
+            auto l = j, r = j;
+            l["autoCorrectReplacements"]["helo"] = "hello";
+            r["autoCorrectReplacements"]["wrold"] = "world";
+            auto paired = mergeSyncSettings(base, bytes(l), bytes(r));
+            require(parse(paired)["autoCorrectReplacements"].size() == 2, "independent replacement pairs merge");
+            l = r = parse(paired);
+            l["autoCorrectReplacements"].erase("helo");
+            r["autoCorrectReplacements"]["wrold"] = "worlds";
+            auto removed = mergeSyncSettings(paired, bytes(l), bytes(r));
+            auto restored = restoreSyncSettings(removed, local, {});
+            require(restored.autoReplacements.size() == 1 && restored.autoReplacements.at(L"wrold") == L"worlds",
+                    "replacement deletion merges with an independent edit and remains loadable");
+            r["autoCorrectReplacements"]["helo"] = "help";
+            require(mergeSyncProfile(paired, bytes(l), bytes(r)).conflicts.size() == 1,
+                    "replacement deletion versus edit is a conflict");
+            auto legacy = j;
+            for (auto key : {"autoCorrectReplace", "autoCorrectTypos", "autoCorrectReplacements"}) legacy.erase(key);
+            auto migrated = restoreSyncSettings(bytes(legacy), local, {});
+            require(!migrated.autoReplace && !migrated.autoTypos && migrated.autoReplacements.empty(),
+                    "older synchronized profiles default new typo modes off");
+        }
         {
             auto l = j, r = j;
             l["autoCorrectMinLength"] = 4; r["autoCorrectMinLength"] = 5;
@@ -173,6 +217,40 @@ int main()
         rejects([&] { synchronize(provider, base, bytes(left), SyncAction::Upload); }, "racing writer protected");
         require(provider.writes == 1 && provider.remote.settings == base, "CAS failure preserves remote");
         provider.race = false;
+        {
+            auto remoteProfile = j;
+            remoteProfile["layouts"] = Json::array({"win:00000422"});
+            remoteProfile["layoutHotkeys"] = Json::array({{{"layoutId", "win:00000422"}, {"hotkey", "Ctrl+Alt+9"}}});
+            remoteProfile["autoCorrectNever"].push_back("remoteword");
+            FakeProvider partial;
+            partial.remote = {3, bytes(remoteProfile)};
+            auto validate = [&](const Bytes &b) { restoreSyncSettings(b, local, {}, true); };
+            auto result = synchronize(partial, {}, base, SyncAction::Automatic, validate, {}, true);
+            auto restored = restoreSyncSettings(result.settings, local, {}, true);
+            require(restored.cycle == local.cycle && restored.direct == local.direct &&
+                    restored.autoNever == std::vector<std::wstring>{L"remoteword"},
+                    "partial sync restores other settings and keeps local layout configuration");
+            auto next = sharedSyncSettings(restored);
+            result = synchronize(partial, result.base, next, SyncAction::Automatic, validate, {}, true);
+            require(parse(partial.remote.settings)["layouts"] == remoteProfile["layouts"] &&
+                    parse(partial.remote.settings)["layoutHotkeys"] == remoteProfile["layoutHotkeys"],
+                    "repeated partial sync never deletes unavailable server layouts or shortcuts");
+            auto changed = parse(next); changed["autoCorrectMinLength"] = 7;
+            result = synchronize(partial, result.base, bytes(changed), SyncAction::Upload, validate, {}, true);
+            require(parse(partial.remote.settings)["autoCorrectMinLength"] == 7 &&
+                    parse(partial.remote.settings)["layoutHotkeys"] == remoteProfile["layoutHotkeys"],
+                    "explicit partial upload preserves server layouts too");
+            auto downloaded = synchronize(partial, result.base, base, SyncAction::Download, validate, {}, true);
+            auto downloadedSettings = restoreSyncSettings(downloaded.settings, local, {}, true);
+            require(downloadedSettings.autoMinLength == 7 && downloadedSettings.cycle == local.cycle &&
+                    downloadedSettings.direct == local.direct, "partial Download applies other settings without replacing local layouts");
+            try { restoreSyncSettings(bytes(remoteProfile), local, {}); require(false, "full sync must identify missing layouts"); }
+            catch (const std::runtime_error &e) {
+                std::string message = e.what();
+                require(message.find("win:00000422") != message.npos && message.find("Keep this PC's layouts") != message.npos,
+                        "missing-layout error identifies IDs and offers partial sync");
+            }
+        }
         rejects([&] { synchronize(provider, base, bytes(left), SyncAction::Upload,
             [](const Bytes &) { throw std::runtime_error("invalid"); }); }, "validate before upload");
         require(provider.writes == 1, "invalid data not uploaded");

tests/tests.cpp

@@ -111,8 +111,8 @@ int main(int argc, char **argv)
         require(diagnostics.record(L"later-failure", true, 30500).find(L"expired-context") == std::wstring::npos,
                 "context expires after thirty seconds");
         diagnostics.record(L"oldest-context", false, 30600);
-        for (int i = 0; i < 40; ++i)
-            diagnostics.record(L"bounded-context", false, 30600 + i);
+        for (int i = 0; i < 128; ++i)
+            diagnostics.record(L"bounded-context", false, 30600);
         require(diagnostics.record(L"bounded-failure", true, 30700).find(L"oldest-context") == std::wstring::npos,
                 "context buffer has a fixed size");
         diagnostics.record(L"disabled-context", false, 30800);
@@ -217,6 +217,13 @@ 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);
+        {
+            auto options = autoSettings;
+            options.autoTypos = true;
+            auto typo = corrector.suggest(L"првиіт ", 2, layouts, options);
+            require(typo && typo->text == L"привіт " && typo->target == 2,
+                    "bundled Ukrainian dictionary corrects a common transposition");
+        }
         auto suggested = corrector.suggest(L"ghbdsn ", 0, layouts, autoSettings);
         require(suggested && suggested->text == L"привіт " && suggested->target == 2,
                 "dictionary corrects Ukrainian and retains trailing space");
@@ -497,6 +504,45 @@ int main(int argc, char **argv)
             auto correction = edited.suggest(L"руддщ ", 2, layouts, options);
             require(correction && correction->text == L"hello ",
                     "unsorted dictionaries and duplicates load using lowest duplicate rank");
+            require(!edited.suggest(L"hlelo ", 0, layouts, options), "spelling correction defaults off");
+            options.autoTypos = true;
+            for (auto typo : {L"hlelo ", L"helo ", L"helllo ", L"hezlo "})
+            {
+                correction = edited.suggest(typo, 0, layouts, options);
+                require(correction && correction->text == L"hello " && correction->target == 0,
+                        "single transposition, deletion, insertion and substitution retain the source layout");
+            }
+            correction = edited.suggest(L"(Hlelo), ", 0, layouts, options);
+            require(correction && correction->text == L"(Hello), ", "typos retain case and punctuation");
+            for (auto text : {L"hello ", L"HLELO ", L"hLelo ", L"h3llo ", L"h.llo ", L"hlo ", L"hello@example.com "})
+                require(!edited.suggest(text, 0, layouts, options), "known or unsafe typo input is unchanged");
+            options.autoWords[L"en"] = {L"hella"};
+            require(!edited.suggest(L"hell ", 0, layouts, options), "personal dictionary alternatives create ambiguity");
+            options.autoWords.clear();
+            options.autoReplacements = {{L"hlelo", L"greeting"}, {L"hello", L"greetings"}, {L"првиіт", L"привіт"}};
+            options.autoReplace = true;
+            correction = edited.suggest(L"Hlelo! ", 0, layouts, options);
+            require(correction && correction->text == L"Greeting! ", "explicit replacements override spelling guesses");
+            correction = edited.suggest(L"hello ", 0, layouts, options);
+            require(correction && correction->text == L"greetings ", "explicit replacements can override known words");
+            correction = edited.suggest(L"Првиіт ", 2, layouts, options);
+            require(correction && correction->text == L"Привіт " && correction->target == 2,
+                    "Ukrainian replacements work without dictionary membership");
+            options.autoNever = {L"hlelo"};
+            require(!edited.suggest(L"hlelo ", 0, layouts, options), "never-correct overrides explicit pairs");
+            options.autoNever.clear();
+            edited.reject(L"(Hlelo)! ", options);
+            require(!edited.suggest(L"hlelo ", 0, layouts, options), "undo rejection suppresses custom replacements");
+            options.autoReplace = false;
+            options.autoWords[L"uk"] = {L"привіт"};
+            correction = edited.suggest(L"првиіт ", 2, layouts, options);
+            require(correction && correction->text == L"привіт ", "Ukrainian personal words are typo targets");
+            options.cycle = {L"en"};
+            require(!edited.suggest(L"првиіт ", 2, layouts, options), "disabled source layouts do not correct typos");
+            put(L"en.txt", L"hello\t1\nhella\t99999\n");
+            ks::AutoCorrector ambiguous;
+            ambiguous.configure(folder, {L"en", L"uk"});
+            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}};
         ks::Clip firstImage{{ks::imageDib(pixels), {0, L"Ole Private Data", {1, 2, 3}}}};
@@ -542,6 +588,8 @@ int main(int argc, char **argv)
         settings.writeLog = false;
         settings.elevatedAutostart = true;
         settings.autoCorrect = true;
+        settings.autoReplace = settings.autoTypos = true;
+        settings.autoReplacements = {{L"првиіт", L"привіт"}, {L"helo", L"hello"}};
         settings.autoMaxRank = 10000;
         settings.autoMinLength = 5;
         settings.autoPrefixChars = L"(#";
@@ -554,6 +602,14 @@ int main(int argc, char **argv)
         ks::saveSettings(temp / L"settings.json", settings);
         auto restored = ks::loadSettings(temp / L"settings.json", {});
         require(restored.autoWords == settings.autoWords, "personal dictionaries survive settings roundtrip");
+        require(restored.autoReplace && restored.autoTypos && restored.autoReplacements == settings.autoReplacements,
+                "typo options and Unicode pairs survive settings roundtrip");
+        for (const auto &pair : {std::pair{L"hello", L"привіт"}, {L"hello", L"hello"}, {L"hi!", L"hello"}})
+        {
+            auto invalid = settings;
+            invalid.autoReplacements = {{pair.first, pair.second}};
+            rejects([&] { ks::validateSettings(invalid); }, "invalid replacement pairs rejected");
+        }
         auto invalidWords = settings;
         invalidWords.autoWords[L"uk"] = {L"hello"};
         rejects([&] { ks::validateSettings(invalidWords); }, "personal dictionary rejects wrong language letters");