Merge pull request #2534 from openchamber/feat/bc-38abb61a-bce6-4a01-a189-c569346927fa-33b6

fix(files): stop autosave data loss on load lag and binary files

packages/ui/src/apps/MobileFilesSurface.tsx

@@ -28,7 +28,7 @@ import { copyTextToClipboard } from '@/lib/clipboard';
 import { useI18n } from '@/lib/i18n';
 import { ensurePierreThemeRegistered } from '@/lib/shiki/appThemeRegistry';
 import { getDefaultTheme } from '@/lib/theme/themes';
-import { getImageMimeType, getLanguageFromExtension, isImageFile } from '@/lib/toolHelpers';
+import { getImageMimeType, getLanguageFromExtension, isBinaryFile, isImageFile, isPdfFile, isSvgFile, looksLikeBinaryText } from '@/lib/toolHelpers';
 import type { FileListEntry, FileSearchResult } from '@/lib/api/types';
 import { runtimeFetch } from '@/lib/runtime-fetch';
 import { cn } from '@/lib/utils';
@@ -98,6 +98,7 @@ export const MobileFilesSurface: React.FC<MobileFilesSurfaceProps> = ({ onClose
   const [imageSrc, setImageSrc] = React.useState('');
   const [fileError, setFileError] = React.useState<string | null>(null);
   const [isLoadingFile, setIsLoadingFile] = React.useState(false);
+  const [binaryBlocked, setBinaryBlocked] = React.useState(false);
   const directoryLoadRequestIdRef = React.useRef(0);
 
   React.useEffect(() => {
@@ -174,8 +175,9 @@ export const MobileFilesSurface: React.FC<MobileFilesSurfaceProps> = ({ onClose
     setFileContent('');
     setImageSrc('');
     setFileError(null);
+    setBinaryBlocked(false);
 
-    if (isImageFile(route.path) && !route.path.toLowerCase().endsWith('.svg')) {
+    if (isImageFile(route.path) && !isSvgFile(route.path)) {
       let cancelled = false;
       let objectUrl = '';
       setIsLoadingFile(true);
@@ -203,6 +205,14 @@ export const MobileFilesSurface: React.FC<MobileFilesSurfaceProps> = ({ onClose
       };
     }
 
+    // Never load PDF/office/archives/etc. as UTF-8 text — that path can corrupt originals
+    // if a future write path is added, and it shows gibberish in the viewer.
+    if (isBinaryFile(route.path) || isPdfFile(route.path)) {
+      setBinaryBlocked(true);
+      setIsLoadingFile(false);
+      return;
+    }
+
     if (!files.readFile) {
       setFileError(t('mobile.files.error.readUnavailable'));
       setIsLoadingFile(false);
@@ -214,6 +224,11 @@ export const MobileFilesSurface: React.FC<MobileFilesSurfaceProps> = ({ onClose
     void files.readFile(route.path)
       .then((result) => {
         if (cancelled) return;
+        if (looksLikeBinaryText(result.content)) {
+          setBinaryBlocked(true);
+          setFileContent('');
+          return;
+        }
         setFileContent(result.content.length > MAX_MOBILE_FILE_CHARS
           ? `${result.content.slice(0, MAX_MOBILE_FILE_CHARS)}\n\n${t('mobile.files.file.truncated')}`
           : result.content);
@@ -263,6 +278,7 @@ export const MobileFilesSurface: React.FC<MobileFilesSurfaceProps> = ({ onClose
         imageSrc={imageSrc}
         error={fileError}
         isLoading={isLoadingFile}
+        binaryBlocked={binaryBlocked}
         onBack={() => setRoute({ type: 'browser', directory: route.returnDirectory })}
         onCopyPath={() => void handleCopyPath(route.path)}
         onCopyContent={() => void handleCopyContent()}
@@ -413,10 +429,11 @@ const MobileFileDetail: React.FC<{
   imageSrc: string;
   error: string | null;
   isLoading: boolean;
+  binaryBlocked: boolean;
   onBack: () => void;
   onCopyPath: () => void;
   onCopyContent: () => void;
-}> = ({ path, content, imageSrc, error, isLoading, onBack, onCopyPath, onCopyContent }) => {
+}> = ({ path, content, imageSrc, error, isLoading, binaryBlocked, onBack, onCopyPath, onCopyContent }) => {
   const { t } = useI18n();
 
   return (
@@ -433,7 +450,7 @@ const MobileFileDetail: React.FC<{
         <div className="min-w-0 flex-1">
           <h2 className="truncate typography-ui-header text-foreground">{getNameFromPath(path)}</h2>
         </div>
-        {!isImageFile(path) ? (
+        {!isImageFile(path) && !binaryBlocked ? (
           <Button type="button" variant="ghost" size="icon" onClick={onCopyContent} aria-label={t('mobile.files.copyContentAria')}>
             <RiFileCopyLine className="size-4" />
           </Button>
@@ -455,6 +472,11 @@ const MobileFileDetail: React.FC<{
           <ScrollShadow className="h-full overflow-auto p-4">
             <img src={`data:${getImageMimeType(path)};utf8,${encodeURIComponent(content)}`} alt={getNameFromPath(path)} className="mx-auto max-h-full max-w-full rounded-lg object-contain" />
           </ScrollShadow>
+        ) : binaryBlocked ? (
+          <div className="flex h-full flex-col items-center justify-center gap-2 p-6 text-center">
+            <div className="typography-ui-header text-foreground">{t('filesView.editor.cannotPreviewBinary')}</div>
+            <div className="max-w-sm typography-ui text-muted-foreground">{t('filesView.editor.binaryFileDescription')}</div>
+          </div>
         ) : (
           <MobileTextFile path={path} content={content} />
         )}

packages/ui/src/components/layout/SidebarFilesTree.tsx

@@ -868,7 +868,7 @@ export const SidebarFilesTree: React.FC = () => {
   const handleOpenFile = React.useCallback(async (node: FileNode) => {
     if (!root) return;
 
-    const openValidation = await validateContextFileOpen(files, node.path);
+    const openValidation = await validateContextFileOpen(files, node.path, { directory: root });
     if (!openValidation.ok) {
       toast.error(getContextFileOpenFailureMessage(openValidation.reason));
       return;

packages/ui/src/components/sections/openchamber/OpenChamberPage.tsx

@@ -146,6 +146,7 @@ const GeneralSectionContent: React.FC = () => {
             {!isVSCode && <OpenCodeCliSettings />}
             <OpenChamberVisualSettings visibleSettings={[
                 'fileEditorKeymap',
+                'autoSaveEnabled',
                 'expandedEditorToolbar',
                 ...(!isVSCode ? ['terminalQuickKeys' as const] : []),
                 ...(!isVSCode ? ['terminalShell' as const] : []),

packages/ui/src/components/sections/openchamber/OpenChamberVisualSettings.tsx

@@ -279,7 +279,7 @@ const normalizeUserMessageRenderingMode = (mode: unknown): 'markdown' | 'plain'
     return mode === 'markdown' ? 'markdown' : 'plain';
 };
 
-type VisibleSetting = 'sessionAssist' | 'sessionGoal' | 'theme' | 'windowControlsPosition' | 'pwaInstallName' | 'pwaOrientation' | 'mobileKeyboardMode' | 'timeFormat' | 'weekStart' | 'fontSize' | 'terminalFontSize' | 'terminalShell' | 'terminalLoginShell' | 'editorFontSize' | 'spacing' | 'inputBarOffset' | 'mermaidRendering' | 'userMessageRendering' | 'chatRenderMode' | 'messageTransport' | 'activityRenderMode' | 'collapsibleUserMessages' | 'stickyUserHeader' | 'promptNavigatorEnabled' | 'wideChatLayout' | 'codeBlockLineWrap' | 'splitAssistantMessageActions' | 'subagentReadOnlyBanner' | 'diffLayout' | 'mobileStatusBar' | 'dotfiles' | 'fileViewerPreview' | 'reasoning' | 'showToolFileIcons' | 'showTurnChangedFiles' | 'expandedTools' | 'followUpBehavior' | 'terminalQuickKeys' | 'fileEditorKeymap' | 'persistDraft' | 'inputSpellcheck' | 'reportUsage' | 'expandedEditorToolbar';
+type VisibleSetting = 'sessionAssist' | 'sessionGoal' | 'theme' | 'windowControlsPosition' | 'pwaInstallName' | 'pwaOrientation' | 'mobileKeyboardMode' | 'timeFormat' | 'weekStart' | 'fontSize' | 'terminalFontSize' | 'terminalShell' | 'terminalLoginShell' | 'editorFontSize' | 'spacing' | 'inputBarOffset' | 'mermaidRendering' | 'userMessageRendering' | 'chatRenderMode' | 'messageTransport' | 'activityRenderMode' | 'collapsibleUserMessages' | 'stickyUserHeader' | 'promptNavigatorEnabled' | 'wideChatLayout' | 'codeBlockLineWrap' | 'splitAssistantMessageActions' | 'subagentReadOnlyBanner' | 'diffLayout' | 'mobileStatusBar' | 'dotfiles' | 'fileViewerPreview' | 'reasoning' | 'showToolFileIcons' | 'showTurnChangedFiles' | 'expandedTools' | 'followUpBehavior' | 'terminalQuickKeys' | 'fileEditorKeymap' | 'persistDraft' | 'inputSpellcheck' | 'reportUsage' | 'expandedEditorToolbar' | 'autoSaveEnabled';
 
 const WINDOW_CONTROLS_POSITION_OPTIONS: Array<{ id: DesktopWindowControlsPosition; labelKey: string }> = [
     { id: 'left', labelKey: 'settings.openchamber.desktopNetwork.option.windowControlsLeft' },
@@ -330,6 +330,8 @@ export const OpenChamberVisualSettings: React.FC<OpenChamberVisualSettingsProps>
     const setPromptNavigatorEnabled = useUIStore(state => state.setPromptNavigatorEnabled);
     const expandedEditorToolbar = useUIStore(state => state.expandedEditorToolbar);
     const setExpandedEditorToolbar = useUIStore(state => state.setExpandedEditorToolbar);
+    const autoSaveEnabled = useUIStore(state => state.autoSaveEnabled);
+    const setAutoSaveEnabled = useUIStore(state => state.setAutoSaveEnabled);
     const wideChatLayoutEnabled = useUIStore(state => state.wideChatLayoutEnabled);
     const setWideChatLayoutEnabled = useUIStore(state => state.setWideChatLayoutEnabled);
     const codeBlockLineWrap = useUIStore(state => state.codeBlockLineWrap);
@@ -643,7 +645,7 @@ export const OpenChamberVisualSettings: React.FC<OpenChamberVisualSettingsProps>
         ? hasLocalizationSettings
         : (shouldShow('theme') || showWindowControlsPositionSetting || showMobileLayoutSetting || shouldShow('pwaInstallName') || shouldShow('pwaOrientation') || shouldShow('timeFormat') || shouldShow('weekStart'));
     const hasLayoutSettings = shouldShow('fontSize') || shouldShow('terminalFontSize') || shouldShow('editorFontSize') || shouldShow('spacing') || (shouldShow('inputBarOffset') && isMobile);
-    const hasNavigationSettings = (shouldShow('terminalQuickKeys') && !isMobile) || ((shouldShow('terminalShell') || shouldShow('terminalLoginShell')) && !isVSCode) || shouldShow('fileEditorKeymap') || (shouldShow('expandedEditorToolbar') && !isVSCode);
+    const hasNavigationSettings = (shouldShow('terminalQuickKeys') && !isMobile) || ((shouldShow('terminalShell') || shouldShow('terminalLoginShell')) && !isVSCode) || shouldShow('fileEditorKeymap') || shouldShow('autoSaveEnabled') || (shouldShow('expandedEditorToolbar') && !isVSCode);
     const hasBehaviorSettings = shouldShow('mermaidRendering')
         || (shouldShow('sessionGoal') && !isVSCode)
         || shouldShow('userMessageRendering')
@@ -1515,6 +1517,16 @@ export const OpenChamberVisualSettings: React.FC<OpenChamberVisualSettingsProps>
                             </SettingsControlGroup>
                         )}
                         <div className={SETTINGS_OPTION_STACK_CLASS}>
+                            {shouldShow('autoSaveEnabled') && (
+                                <SettingsCheckboxRow
+                                    checked={autoSaveEnabled}
+                                    onChange={setAutoSaveEnabled}
+                                    label={t('settings.openchamber.visual.field.autoSaveEnabled')}
+                                    ariaLabel={t('settings.openchamber.visual.field.autoSaveEnabledAria')}
+                                    info={t('settings.openchamber.visual.field.autoSaveEnabledInfo')}
+                                    settingsItem="appearance.auto-save-enabled"
+                                />
+                            )}
                             {shouldShow('expandedEditorToolbar') && !isVSCode && (
                                 <SettingsCheckboxRow
                                     checked={expandedEditorToolbar}

packages/ui/src/components/ui/CommandPalette.tsx

@@ -455,7 +455,7 @@ export const CommandPalette: React.FC = () => {
   const handleOpenFile = React.useCallback(
     async (filePath: string) => {
       if (!currentRoot) return;
-      const validation = await validateContextFileOpen(filesApi, filePath);
+      const validation = await validateContextFileOpen(filesApi, filePath, { directory: currentRoot });
       if (!validation.ok) {
         toast.error(getContextFileOpenFailureMessage(validation.reason));
         return;

packages/ui/src/components/views/DiffView.tsx

@@ -1537,7 +1537,7 @@ export const DiffView: React.FC<DiffViewProps> = ({
                 : getFirstChangedModifiedLine(diffForNavigation.original, diffForNavigation.modified));
 
             const absolutePath = toAbsolutePath(effectiveDirectory, filePath);
-            const openValidation = await validateContextFileOpen(files, absolutePath);
+            const openValidation = await validateContextFileOpen(files, absolutePath, { directory: effectiveDirectory });
             if (!openValidation.ok) {
                 toast.error(getContextFileOpenFailureMessage(openValidation.reason));
                 return;

packages/ui/src/components/views/FilesView.tsx

@@ -44,7 +44,8 @@ import { useDebouncedValue } from '@/hooks/useDebouncedValue';
 import { useFileSearchStore } from '@/stores/useFileSearchStore';
 import { useDeviceInfo } from '@/lib/device';
 import { cn, getModifierLabel, getRevealLabelKey, hasModifier } from '@/lib/utils';
-import { getLanguageFromExtension, getImageMimeType, isDrawioFile, isImageFile, isPdfFile } from '@/lib/toolHelpers';
+import { getLanguageFromExtension, getImageMimeType, isBinaryFile, isDrawioFile, isImageFile, isPdfFile, isSvgFile, looksLikeBinaryText } from '@/lib/toolHelpers';
+import { shouldAllowFileDraftSave, shouldScheduleFileAutosave } from '@/lib/fileEditorAutosave';
 import { getRuntimeUrlResolver } from '@/lib/runtime-url';
 import { acquireRuntimeUrlAuthToken, refreshRuntimeUrlAuthToken, subscribeRuntimeUrlAuthToken } from '@/lib/runtime-auth';
 import { getRuntimeApiBaseUrl } from '@/lib/runtime-switch';
@@ -304,7 +305,6 @@ const isFileMissingError = (error: unknown): boolean => {
 };
 
 const MAX_VIEW_CHARS = 200_000;
-const FILE_EDITOR_AUTO_SAVE_KEY = 'openchamber:files:auto-save-enabled';
 type FileLineEnding = '\n' | '\r\n';
 
 const detectFileLineEnding = (content: string): FileLineEnding => {
@@ -332,18 +332,6 @@ const serializeEditorContent = (content: string, lineEnding: FileLineEnding): st
   return lineEnding === '\r\n' ? normalized.replace(/\n/g, '\r\n') : normalized;
 };
 
-const getInitialAutoSaveEnabled = (): boolean => {
-  if (typeof window === 'undefined') {
-    return true;
-  }
-
-  try {
-    return window.localStorage.getItem(FILE_EDITOR_AUTO_SAVE_KEY) !== 'false';
-  } catch {
-    return true;
-  }
-};
-
 const getFileIcon = (filePath: string, extension?: string): React.ReactNode => {
   return <FileTypeIcon filePath={filePath} extension={extension} />;
 };
@@ -924,7 +912,9 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
   const loadingFilePathRef = React.useRef<string | null>(null);
   const [autoSaveStatus, setAutoSaveStatus] = React.useState<'idle' | 'saved'>('idle');
   const [diagramSaved, setDiagramSaved] = React.useState(false);
-  const [autoSaveEnabled, setAutoSaveEnabled] = React.useState(getInitialAutoSaveEnabled);
+  const [contentDetectedBinary, setContentDetectedBinary] = React.useState(false);
+  const autoSaveEnabled = useUIStore((state) => state.autoSaveEnabled);
+  const setAutoSaveEnabled = useUIStore((state) => state.setAutoSaveEnabled);
 
   const [confirmDiscardOpen, setConfirmDiscardOpen] = React.useState(false);
   const pendingSelectFileRef = React.useRef<FileNode | null>(null);
@@ -1626,17 +1616,31 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
       return false;
     }
 
-    if (!isDirty) {
+    const selectedIsBinary = isBinaryFile(selectedFile.path) || contentDetectedBinary;
-      return true;
+    if (!shouldAllowFileDraftSave({
+      selectedFilePath: selectedFile.path,
+      loadedFilePath,
+      fileLoading,
+      isDirty,
+      draftContent,
+      fileContent,
+      isNonEditableBinary: selectedIsBinary,
+    })) {
+      if (selectedIsBinary) {
+        console.warn(`[saveDraft] refusing to save binary file "${selectedFile.path}".`);
+      } else if (draftContent === '' && fileContent !== '' && loadedFilePath !== selectedFile.path) {
+        console.warn(
+          `[saveDraft] refusing to save empty draft for "${selectedFile.path}" (${fileContent.length} bytes were expected). ` +
+          'The file may have been read during a concurrent write (O_TRUNC race). ' +
+          'Try again after content finishes loading if the save was intentional.',
+        );
+      }
+      return false;
     }
 
-    if (draftContent === '' && fileContent !== '' && loadedFilePath !== selectedFile.path) {
+    // Clean draft: treat as success so discard/save dialogs and Ctrl+S are not stranded.
-      console.warn(
+    if (!isDirty) {
-        `[saveDraft] refusing to save empty draft for "${selectedFile.path}" (${fileContent.length} bytes were expected). ` +
+      return true;
-        'The file may have been read during a concurrent write (O_TRUNC race). ' +
-        'Try again after content finishes loading if the save was intentional.',
-      );
-      return false;
     }
 
     setIsSaving(true);
@@ -1668,7 +1672,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
     } finally {
       setIsSaving(false);
     }
-  }, [draftContent, fileContent, files, isDirty, loadedFileLineEnding, loadedFilePath, readFileStat, selectedFile, t]);
+  }, [contentDetectedBinary, draftContent, fileContent, fileLoading, files, isDirty, loadedFileLineEnding, loadedFilePath, readFileStat, selectedFile, t]);
 
   React.useEffect(() => {
     if (!isDirty) {
@@ -1696,14 +1700,6 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
     };
   }, [isDirty, setMainTabGuard]);
 
-  React.useEffect(() => {
-    try {
-      window.localStorage.setItem(FILE_EDITOR_AUTO_SAVE_KEY, autoSaveEnabled ? 'true' : 'false');
-    } catch {
-      // Ignore localStorage errors; the in-memory preference still applies.
-    }
-  }, [autoSaveEnabled]);
-
   React.useEffect(() => {
     if (autoSaveEnabled) {
       return;
@@ -1721,7 +1717,17 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
 
   React.useEffect(() => {
     const canWrite = Boolean(selectedFile && files.writeFile);
-    if (!autoSaveEnabled || !isDirty || !canWrite || isSaving) {
+    const selectedIsBinary = Boolean(selectedFile?.path && (isBinaryFile(selectedFile.path) || contentDetectedBinary));
+    if (!shouldScheduleFileAutosave({
+      autoSaveEnabled,
+      isDirty,
+      canWrite,
+      isSaving,
+      fileLoading,
+      selectedFilePath: selectedFile?.path,
+      loadedFilePath,
+      isNonEditableBinary: selectedIsBinary,
+    })) {
       return;
     }
 
@@ -1739,7 +1745,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
         autoSaveTimerRef.current = null;
       }
     };
-  }, [autoSaveEnabled, draftContent, isDirty, selectedFile, files.writeFile, isSaving, saveDraft]);
+  }, [autoSaveEnabled, contentDetectedBinary, draftContent, fileLoading, isDirty, loadedFilePath, selectedFile, files.writeFile, isSaving, saveDraft]);
 
   // Reset auto-save status when switching files
   React.useEffect(() => {
@@ -1789,10 +1795,12 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
     setFileError(null);
     setDesktopImageSrc('');
     setLoadedFilePath(null);
+    setContentDetectedBinary(false);
 
     const selectedIsImage = isImageFile(node.path);
-    const isSvg = node.path.toLowerCase().endsWith('.svg');
+    const isSvg = isSvgFile(node.path);
     const selectedIsPdf = isPdfFile(node.path);
+    const selectedIsBinary = isBinaryFile(node.path);
 
     if (isMobile) {
       setShowMobilePageContent(true);
@@ -1823,6 +1831,16 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
       return;
     }
 
+    // Other known binaries (docx/xlsx/zip/…) must never be opened as text —
+    // a later autosave would corrupt them.
+    if (selectedIsBinary) {
+      setFileContent('');
+      setDraftContent('');
+      setLoadedFilePath(node.path);
+      setFileLoading(false);
+      return;
+    }
+
     setFileLoading(true);
 
     const outsideFileGrant = getOutsideFileGrant(node.path);
@@ -1836,6 +1854,13 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
         if (!isCurrentLoad()) {
           return;
         }
+        if (looksLikeBinaryText(content)) {
+          setContentDetectedBinary(true);
+          setFileContent('');
+          setDraftContent('');
+          setLoadedFilePath(node.path);
+          return;
+        }
         const editorContent = normalizeEditorLineEndings(content);
         setLoadedFileLineEnding(detectFileLineEnding(content));
         setFileContent(editorContent);
@@ -2302,8 +2327,13 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
   }
 
   const isSelectedImage = Boolean(selectedFile?.path && isImageFile(selectedFile.path));
-  const isSelectedSvg = Boolean(selectedFile?.path && selectedFile.path.toLowerCase().endsWith('.svg'));
+  const isSelectedSvg = Boolean(selectedFile?.path && isSvgFile(selectedFile.path));
   const isSelectedPdf = Boolean(selectedFile?.path && isPdfFile(selectedFile.path));
+  const isSelectedBinary = Boolean(
+    selectedFile?.path
+    && (isBinaryFile(selectedFile.path) || contentDetectedBinary)
+  );
+  const isUnsupportedBinary = isSelectedBinary && !isSelectedImage && !isSelectedPdf;
   const pendingNavigationTargetPath = React.useMemo(
     () => normalizePath(pendingFileNavigation?.path ?? ''),
     [pendingFileNavigation?.path],
@@ -2316,21 +2346,24 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
       && !fileLoading
       && !fileError
       && !isSelectedImage
-      && !isSelectedPdf,
+      && !isSelectedPdf
+      && !isUnsupportedBinary,
   );
 
   const displaySelectedPath = React.useMemo(() => {
     return getDisplayPath(root, selectedFilePath);
   }, [selectedFilePath, root]);
 
-  const canCopy = Boolean(selectedFile && (!isSelectedImage || isSelectedSvg) && !isSelectedPdf && fileContent.length > 0);
+  const canCopy = Boolean(selectedFile && (!isSelectedImage || isSelectedSvg) && !isSelectedPdf && !isUnsupportedBinary && fileContent.length > 0);
   const canCopyPath = Boolean(selectedFile && displaySelectedPath.length > 0);
-  const canEdit = Boolean(selectedFile && !selectedFileIsOutsideWorkspace && !isSelectedImage && !isSelectedPdf && files.writeFile && fileContent.length <= MAX_VIEW_CHARS);
+  // Keep image/SVG on the preview path: `isBinaryFile` excludes `.svg`, so binary
+  // alone would flip canEdit/isTextFile true and show a dead edit toggle + no-op Save.
+  const canEdit = Boolean(selectedFile && !selectedFileIsOutsideWorkspace && !isSelectedBinary && !isSelectedImage && files.writeFile && fileContent.length <= MAX_VIEW_CHARS);
   const isMarkdown = Boolean(selectedFile?.path && isMarkdownFile(selectedFile.path));
   const isJson = Boolean(selectedFile?.path && isJsonFile(selectedFile.path));
   const isHtml = Boolean(selectedFile?.path && isHtmlFile(selectedFile.path));
   const isDrawio = Boolean(selectedFile?.path && isDrawioFile(selectedFile.path));
-  const isTextFile = Boolean(selectedFile && !isSelectedImage && !isSelectedPdf);
+  const isTextFile = Boolean(selectedFile && !isSelectedBinary && !isSelectedImage);
   const canUseShikiFileView = isTextFile && !isMarkdown && !isDrawio && !(isHtml && htmlViewMode === 'preview');
   const isEditingFile = (isMarkdown && mdViewMode === 'edit')
     || (isHtml && htmlViewMode === 'edit')
@@ -2535,7 +2568,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
 
   const handleDiagramChange = React.useCallback((xml: string) => {
     diagramXmlRef.current = xml;
-    if (!selectedFile?.path || drawioViewMode !== 'preview' || !files.writeFile) {
+    if (!autoSaveEnabled || !selectedFile?.path || drawioViewMode !== 'preview' || !files.writeFile) {
       return;
     }
 
@@ -2554,7 +2587,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
         toast.error(error instanceof Error ? error.message : t('filesView.toast.saveFailed'));
       });
     }, AUTO_SAVE_DELAY);
-  }, [drawioViewMode, files.writeFile, saveDiagramXml, selectedFile?.path, t]);
+  }, [autoSaveEnabled, drawioViewMode, files.writeFile, saveDiagramXml, selectedFile?.path, t]);
 
   const diagramEditorXml = React.useMemo(() => {
     if (!isDrawio) {
@@ -2674,7 +2707,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
       return;
     }
 
-    if (fileError || isSelectedImage || isSelectedPdf) {
+    if (fileError || isSelectedImage || isSelectedPdf || isUnsupportedBinary) {
       setPendingFileNavigation(null);
       pendingNavigationCycleRef.current = { key: '', attempts: 0 };
       return;
@@ -2746,6 +2779,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
     fileLoading,
     isSelectedImage,
     isSelectedPdf,
+    isUnsupportedBinary,
     loadedFilePath,
     handleSelectFile,
     pendingFileNavigation,
@@ -2783,7 +2817,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
     // JSON tree, images, PDFs) never mount a CodeMirror editor, so the request
     // must clear regardless — otherwise it lingers and replays on every
     // dependency change.
-    if (!fileError && !isSelectedImage && !isSelectedPdf && canEdit && textViewMode === 'edit') {
+    if (!fileError && !isSelectedImage && !isSelectedPdf && !isUnsupportedBinary && canEdit && textViewMode === 'edit') {
       editorViewRef.current?.focus();
     }
 
@@ -2794,6 +2828,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
     fileLoading,
     isSelectedImage,
     isSelectedPdf,
+    isUnsupportedBinary,
     loadedFilePath,
     pendingFileFocusPath,
     root,
@@ -3189,7 +3224,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
               <Button
                 variant="ghost"
                 size="sm"
-                onClick={() => setAutoSaveEnabled((enabled) => !enabled)}
+                onClick={() => setAutoSaveEnabled(!autoSaveEnabled)}
                 className={cn(
                   'size-6 p-0 transition-opacity hover:bg-transparent focus-visible:bg-transparent active:bg-transparent',
                   autoSaveEnabled ? 'text-foreground opacity-100' : 'text-muted-foreground opacity-65 hover:opacity-100'
@@ -3245,7 +3280,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
           </DropdownMenuContent>
         </DropdownMenu>
 
-        {!isSelectedImage && !isSelectedPdf && (
+        {!isSelectedImage && !isSelectedPdf && !isUnsupportedBinary && (
           <>
             {withTooltip(wrapLines ? t('filesView.editor.disableLineWrap') : t('filesView.editor.enableLineWrap'),
               <Button
@@ -3826,6 +3861,29 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
             </div>
           ) : isSelectedPdf ? (
             renderPdfPreview(selectedFile)
+          ) : isUnsupportedBinary ? (
+            <div className="flex h-full flex-col items-center justify-center gap-3 p-6 text-center">
+              <div className="typography-ui-header text-foreground">{t('filesView.editor.cannotPreviewBinary')}</div>
+              <div className="max-w-md typography-ui text-muted-foreground">{t('filesView.editor.binaryFileDescription')}</div>
+              {files.downloadFile ? (
+                <Button
+                  type="button"
+                  variant="outline"
+                  size="sm"
+                  onClick={() => {
+                    const fn = files.downloadFile;
+                    if (!fn || !selectedFile) return;
+                    void fn(selectedFile.path).catch((error) => {
+                      console.error('Download failed:', error);
+                      toast.error(t('sidebarFilesTree.toast.operationFailed'));
+                    });
+                  }}
+                >
+                  <Icon name="download" className="mr-2 size-4" />
+                  {t('filesView.editor.saveFile')}
+                </Button>
+              ) : null}
+            </div>
           ) : selectedFile && isDrawio && drawioViewMode === 'preview' ? (
             <div className="h-full overflow-hidden" style={{ minHeight: '400px' }}>
               <DiagramEditor
@@ -4197,6 +4255,29 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
             </div>
           ) : isSelectedPdf ? (
             renderPdfPreview(selectedFile)
+          ) : isUnsupportedBinary ? (
+            <div className="flex h-full flex-col items-center justify-center gap-3 p-6 text-center">
+              <div className="typography-ui-header text-foreground">{t('filesView.editor.cannotPreviewBinary')}</div>
+              <div className="max-w-md typography-ui text-muted-foreground">{t('filesView.editor.binaryFileDescription')}</div>
+              {files.downloadFile ? (
+                <Button
+                  type="button"
+                  variant="outline"
+                  size="sm"
+                  onClick={() => {
+                    const fn = files.downloadFile;
+                    if (!fn || !selectedFile) return;
+                    void fn(selectedFile.path).catch((error) => {
+                      console.error('Download failed:', error);
+                      toast.error(t('sidebarFilesTree.toast.operationFailed'));
+                    });
+                  }}
+                >
+                  <Icon name="download" className="mr-2 size-4" />
+                  {t('filesView.editor.saveFile')}
+                </Button>
+              ) : null}
+            </div>
           ) : isMarkdown && getMdViewMode() === 'preview' ? (
             <div className="h-full overflow-auto p-4">
               {fileContent.length > 500 * 1024 && (

packages/ui/src/contexts/RuntimeAPIProvider.tsx

@@ -1,17 +1,32 @@
 import React, { type JSX, type ReactNode } from 'react';
 import { RuntimeAPIContext } from '@/contexts/runtimeAPIContext';
-import type { RuntimeAPIs } from '@/lib/api/types';
+import type { FilesAPI, RuntimeAPIs } from '@/lib/api/types';
 import { createContentCachedFiles } from '@/contexts/content-cache-owner';
 
+type ContentCachedFiles = ReturnType<typeof createContentCachedFiles>;
+
 export function RuntimeAPIProvider({ apis, children }: { apis: RuntimeAPIs; children: ReactNode }): JSX.Element {
-  const cachedFiles = React.useMemo(() => createContentCachedFiles(apis.files), [apis.files]);
+  // Effect-owned lifecycle: React Strict Mode dispose+remount must create a fresh
-  React.useEffect(() => () => cachedFiles.dispose(), [cachedFiles]);
+  // owner. useMemo + dispose reused a dead owner and broke text-file opens
+  // (binaries skipped the pre-read, so they still appeared to work).
+  const [cachedOwner, setCachedOwner] = React.useState<ContentCachedFiles | null>(null);
+
+  React.useEffect(() => {
+    const owner = createContentCachedFiles(apis.files);
+    setCachedOwner(owner);
+    return () => {
+      owner.dispose();
+      setCachedOwner((current) => (current === owner ? null : current));
+    };
+  }, [apis.files]);
+
+  const files: FilesAPI = cachedOwner?.files ?? apis.files;
   const cachedApis = React.useMemo<RuntimeAPIs>(
     () => ({
       ...apis,
-      files: cachedFiles.files,
+      files,
     }),
-    [apis, cachedFiles],
+    [apis, files],
   );
   return <RuntimeAPIContext.Provider value={cachedApis}>{children}</RuntimeAPIContext.Provider>;
 }

packages/ui/src/contexts/content-cache-owner.test.ts

@@ -71,4 +71,54 @@ describe("content cache owner", () => {
     expect(second.content).toBe("/b-2")
     owner.dispose()
   })
+
+  test("disposed owners throw on subsequent reads", async () => {
+    const owner = createContentCachedFiles({
+      readFile: async (path: string) => ({ path, content: "value" }),
+      statFile: async () => ({ isFile: true, isDirectory: false, size: 5, mtimeMs: 1 }),
+    } as unknown as FilesAPI)
+
+    owner.dispose()
+    await expect(owner.files.readFile!("notes.txt", { optional: true, directory: "/tmp/project" }))
+      .rejects.toThrow("File cache owner disposed")
+  })
+
+  test("runtime endpoint changes clear cache but keep serving reads", async () => {
+    const originalWindow = globalThis.window
+    const events = new EventTarget()
+    Object.defineProperty(globalThis, "window", {
+      configurable: true,
+      value: {
+        addEventListener: events.addEventListener.bind(events),
+        removeEventListener: events.removeEventListener.bind(events),
+        dispatchEvent: events.dispatchEvent.bind(events),
+      },
+    })
+
+    try {
+      let reads = 0
+      const owner = createContentCachedFiles({
+        readFile: async (path: string) => ({ path, content: `value-${++reads}` }),
+        statFile: async () => ({ isFile: true, isDirectory: false, size: 7, mtimeMs: 1 }),
+      } as unknown as FilesAPI)
+
+      expect((await owner.files.readFile!("notes.txt")).content).toBe("value-1")
+      window.dispatchEvent(new CustomEvent("openchamber:runtime-endpoint-will-change", {
+        detail: {
+          apiBaseUrl: "http://127.0.0.1:3902",
+          previousApiBaseUrl: "http://127.0.0.1:3901",
+          runtimeKey: "url:http://127.0.0.1:3902",
+          previousRuntimeKey: "url:http://127.0.0.1:3901",
+        },
+      }))
+      expect((await owner.files.readFile!("notes.txt")).content).toBe("value-2")
+      expect(reads).toBe(2)
+      owner.dispose()
+    } finally {
+      Object.defineProperty(globalThis, "window", {
+        configurable: true,
+        value: originalWindow,
+      })
+    }
+  })
 })

packages/ui/src/contexts/content-cache-owner.ts

@@ -5,6 +5,14 @@ const MAX_ENTRIES = 40;
 const MAX_BYTES = 20 * 1024 * 1024;
 type Entry = { content: string; path: string; sourcePath: string; size: number; mtimeMs: number; bytes: number };
 
+/**
+ * Content-cached `FilesAPI.readFile` wrapper.
+ *
+ * Lifecycle: `RuntimeAPIProvider` owns create/dispose in an effect so React
+ * Strict Mode remounts get a fresh owner. After `dispose()`, reads throw —
+ * callers must not keep using a torn-down owner. Runtime endpoint switches
+ * bump generation and clear the cache without deactivating the owner.
+ */
 export function createContentCachedFiles(files: FilesAPI): { files: FilesAPI; dispose: () => void } {
   const cache = new Map<string, Entry>();
   let totalBytes = 0;
@@ -32,6 +40,10 @@ export function createContentCachedFiles(files: FilesAPI): { files: FilesAPI; di
     && cached.mtimeMs === latest.mtimeMs
     && cached.size === latest.size
   );
+  const clearCache = () => {
+    cache.clear();
+    totalBytes = 0;
+  };
   const cacheResult = (
     key: string,
     sourcePath: string,
@@ -61,7 +73,7 @@ export function createContentCachedFiles(files: FilesAPI): { files: FilesAPI; di
     const before = await files.statFile?.(path, options).catch(() => null);
     const result = await files.readFile!(path, options);
     const after = await files.statFile?.(path, options).catch(() => null);
-    if (!active) throw new Error('File read invalidated by runtime change');
+    if (!active) throw new Error('File cache owner disposed');
     if (capturedGeneration !== generation) return cachedReadFile!(path, options);
     const stable = before && after && before.isFile && after.isFile
       && before.mtimeMs !== undefined && after.mtimeMs !== undefined
@@ -79,7 +91,7 @@ export function createContentCachedFiles(files: FilesAPI): { files: FilesAPI; di
         const hit = cache.get(key);
         if (!hit) return readFresh(key, path, options, capturedGeneration);
         const latest = await files.statFile?.(path, options).catch(() => null);
-        if (!active) throw new Error('File read invalidated by runtime change');
+        if (!active) throw new Error('File cache owner disposed');
         if (capturedGeneration !== generation) return cachedReadFile!(path, options);
         if (!latest || !metadataMatches(hit, latest)) {
           removeEntry(key);
@@ -116,18 +128,18 @@ export function createContentCachedFiles(files: FilesAPI): { files: FilesAPI; di
   };
   const unsubscribeRuntime = subscribeRuntimeEndpointWillChange((detail) => {
     if (detail.runtimeKey === detail.previousRuntimeKey) return;
-    active = false;
+    // Invalidate cached content for the previous runtime, but keep serving reads.
+    // `apis.files` is typically stable across endpoint switches, so permanently
+    // deactivating this owner would break every subsequent text-file open.
     generation += 1;
-    cache.clear();
+    clearCache();
-    totalBytes = 0;
   });
   return {
     files: cachedFiles,
     dispose: () => {
       active = false;
       generation += 1;
-      cache.clear();
+      clearCache();
-      totalBytes = 0;
       unsubscribeRuntime();
     },
   };

packages/ui/src/lib/api/types.ts

@@ -637,6 +637,7 @@ export interface SettingsPayload {
   nativeNotificationsEnabled?: boolean;
   notificationMode?: 'always' | 'hidden-only';
   autoDeleteEnabled?: boolean;
+  autoSaveEnabled?: boolean;
   autoDeleteAfterDays?: number;
   sessionRetentionAction?: 'archive' | 'delete';
   followUpBehavior?: 'steer' | 'queue';

packages/ui/src/lib/appearanceAutoSave.ts

@@ -31,6 +31,7 @@ type AppearanceSlice = {
   summaryLength: number;
   maxLastMessageLength: number;
   autoDeleteEnabled: boolean;
+  autoSaveEnabled: boolean;
   autoDeleteAfterDays: number;
   sessionRetentionAction: 'archive' | 'delete';
   fontSize: number;
@@ -78,6 +79,7 @@ export const startAppearanceAutoSave = (): void => {
     summaryLength: useUIStore.getState().summaryLength,
     maxLastMessageLength: useUIStore.getState().maxLastMessageLength,
     autoDeleteEnabled: useUIStore.getState().autoDeleteEnabled,
+    autoSaveEnabled: useUIStore.getState().autoSaveEnabled,
     autoDeleteAfterDays: useUIStore.getState().autoDeleteAfterDays,
     sessionRetentionAction: useUIStore.getState().sessionRetentionAction,
     fontSize: useUIStore.getState().fontSize,
@@ -117,6 +119,7 @@ export const startAppearanceAutoSave = (): void => {
       summaryLength: state.summaryLength,
       maxLastMessageLength: state.maxLastMessageLength,
       autoDeleteEnabled: state.autoDeleteEnabled,
+      autoSaveEnabled: state.autoSaveEnabled,
       autoDeleteAfterDays: state.autoDeleteAfterDays,
       sessionRetentionAction: state.sessionRetentionAction,
       fontSize: state.fontSize,
@@ -196,6 +199,9 @@ export const startAppearanceAutoSave = (): void => {
     if (current.autoDeleteEnabled !== previous.autoDeleteEnabled) {
       diff.autoDeleteEnabled = current.autoDeleteEnabled;
     }
+    if (current.autoSaveEnabled !== previous.autoSaveEnabled) {
+      diff.autoSaveEnabled = current.autoSaveEnabled;
+    }
     if (current.autoDeleteAfterDays !== previous.autoDeleteAfterDays) {
       diff.autoDeleteAfterDays = current.autoDeleteAfterDays;
     }

packages/ui/src/lib/contextFileOpenGuard.test.ts

@@ -0,0 +1,37 @@
+import { describe, expect, test } from 'bun:test';
+
+import type { FilesAPI } from '@/lib/api/types';
+import { validateContextFileOpen } from './contextFileOpenGuard';
+
+const filesApi = (content: string): FilesAPI =>
+  ({
+    listDirectory: async () => ({ directory: '/', entries: [] }),
+    readFile: async () => ({ content, path: '/x' }),
+  }) as unknown as FilesAPI;
+
+describe('validateContextFileOpen', () => {
+  test('allows known binaries through without reading text', async () => {
+    const files = {
+      listDirectory: async () => ({ directory: '/', entries: [] }),
+      readFile: async () => {
+        throw new Error('should not read binary as text');
+      },
+    } as unknown as FilesAPI;
+
+    expect(await validateContextFileOpen(files, '/repo/docs/report.pdf')).toEqual({ ok: true });
+    expect(await validateContextFileOpen(files, '/repo/docs/report.docx')).toEqual({ ok: true });
+    expect(await validateContextFileOpen(files, '/repo/docs/pixel.png')).toEqual({ ok: true });
+    expect(await validateContextFileOpen(files, '/repo/bin/archive.zip')).toEqual({ ok: true });
+  });
+
+  test('rejects text payloads that look binary', async () => {
+    expect(await validateContextFileOpen(filesApi('%PDF-1.7\nbinary'), '/repo/mystery.bin.bak')).toEqual({
+      ok: false,
+      reason: 'binary',
+    });
+  });
+
+  test('allows ordinary text files', async () => {
+    expect(await validateContextFileOpen(filesApi('hello\nworld\n'), '/repo/notes.txt')).toEqual({ ok: true });
+  });
+});

packages/ui/src/lib/contextFileOpenGuard.ts

@@ -2,17 +2,22 @@ import type { FilesAPI } from '@/lib/api/types';
 import { MAX_OPEN_FILE_LINES, countLinesWithLimit } from '@/lib/fileOpenLimits';
 import { getCurrentIntlLocale } from '@/lib/i18n';
 import { formatMessage, useI18nStore } from '@/lib/i18n/store';
+import { runtimeFetch } from '@/lib/runtime-fetch';
+import { isBinaryFile, isImageFile, isPdfFile, looksLikeBinaryText } from '@/lib/toolHelpers';
 
 const t = (key: Parameters<typeof formatMessage>[1], params?: Parameters<typeof formatMessage>[2]) =>
   formatMessage(useI18nStore.getState().dictionary, key, params);
-import { runtimeFetch } from '@/lib/runtime-fetch';
 
-export type ContextFileOpenFailureReason = 'too-large' | 'missing' | 'unreadable';
+export type ContextFileOpenFailureReason = 'too-large' | 'missing' | 'unreadable' | 'binary';
 
 export type ContextFileOpenValidationResult =
   | { ok: true }
   | { ok: false; reason: ContextFileOpenFailureReason };
 
+export type ContextFileOpenOptions = {
+  directory?: string;
+};
+
 const classifyReadError = (error: unknown): ContextFileOpenFailureReason => {
   const message = error instanceof Error ? error.message : String(error ?? '');
   const normalized = message.toLowerCase();
@@ -30,16 +35,27 @@ const classifyReadError = (error: unknown): ContextFileOpenFailureReason => {
   return 'unreadable';
 };
 
-const readFileContent = async (files: FilesAPI, path: string): Promise<string> => {
+const readFileContent = async (
+  files: FilesAPI,
+  path: string,
+  options?: ContextFileOpenOptions,
+): Promise<string> => {
   if (files.readFile) {
-    const result = await files.readFile(path, { optional: true });
+    const result = await files.readFile(path, {
+      optional: true,
+      directory: options?.directory,
+    });
     return result.content ?? '';
   }
 
   const params = new URLSearchParams({ path, optional: 'true' });
+  if (options?.directory) {
+    params.set('directory', options.directory);
+  }
   const response = await runtimeFetch(`/api/fs/read?${params.toString()}`, {
     // Avoid conditional requests (304 + empty body).
     cache: 'no-store',
+    headers: options?.directory ? { 'x-opencode-directory': options.directory } : undefined,
   });
   if (!response.ok) {
     const errorPayload = await response.json().catch(() => ({ error: response.statusText }));
@@ -49,9 +65,25 @@ const readFileContent = async (files: FilesAPI, path: string): Promise<string> =
   return response.text();
 };
 
-export const validateContextFileOpen = async (files: FilesAPI, path: string): Promise<ContextFileOpenValidationResult> => {
+/**
+ * Validate whether a context-panel click may open a path in the shared file editor.
+ * Previewable/non-text binaries are allowed through so FilesView can show image/PDF
+ * preview or the cannot-preview empty state — never by decoding them as editable text here.
+ */
+export const validateContextFileOpen = async (
+  files: FilesAPI,
+  path: string,
+  options?: ContextFileOpenOptions,
+): Promise<ContextFileOpenValidationResult> => {
+  if (isBinaryFile(path) || isPdfFile(path) || isImageFile(path)) {
+    return { ok: true };
+  }
+
   try {
-    const content = await readFileContent(files, path);
+    const content = await readFileContent(files, path, options);
+    if (looksLikeBinaryText(content)) {
+      return { ok: false, reason: 'binary' };
+    }
     const lineCount = countLinesWithLimit(content, MAX_OPEN_FILE_LINES);
     if (lineCount > MAX_OPEN_FILE_LINES) {
       return { ok: false, reason: 'too-large' };
@@ -73,5 +105,9 @@ export const getContextFileOpenFailureMessage = (reason: ContextFileOpenFailureR
     return t('contextFileOpen.failure.missing');
   }
 
+  if (reason === 'binary') {
+    return t('filesView.editor.cannotPreviewBinary');
+  }
+
   return t('contextFileOpen.failure.unreadable');
 };

packages/ui/src/lib/desktop.ts

@@ -107,6 +107,7 @@ export type DesktopSettings = {
     renamedGroups?: Record<string, string>;  // groupId -> custom label
   }>;  // Per-provider custom model groups configuration
   autoDeleteEnabled?: boolean;
+  autoSaveEnabled?: boolean;
   autoDeleteAfterDays?: number;
   sessionRetentionAction?: 'archive' | 'delete';
   tunnelProvider?: string;

packages/ui/src/lib/fileEditorAutosave.test.ts

@@ -0,0 +1,60 @@
+import { describe, expect, test } from 'bun:test';
+
+import { shouldAllowFileDraftSave, shouldScheduleFileAutosave } from './fileEditorAutosave';
+
+describe('shouldScheduleFileAutosave', () => {
+  const ready = {
+    autoSaveEnabled: true,
+    isDirty: true,
+    canWrite: true,
+    isSaving: false,
+    fileLoading: false,
+    selectedFilePath: '/repo/a.txt',
+    loadedFilePath: '/repo/a.txt',
+    isNonEditableBinary: false,
+  };
+
+  test('schedules when dirty text file is fully loaded', () => {
+    expect(shouldScheduleFileAutosave(ready)).toBe(true);
+  });
+
+  test('skips while loading or when loaded path mismatches selection', () => {
+    expect(shouldScheduleFileAutosave({ ...ready, fileLoading: true })).toBe(false);
+    expect(shouldScheduleFileAutosave({ ...ready, loadedFilePath: null })).toBe(false);
+    expect(shouldScheduleFileAutosave({ ...ready, loadedFilePath: '/repo/other.txt' })).toBe(false);
+  });
+
+  test('skips when autosave disabled or file is binary', () => {
+    expect(shouldScheduleFileAutosave({ ...ready, autoSaveEnabled: false })).toBe(false);
+    expect(shouldScheduleFileAutosave({ ...ready, isNonEditableBinary: true })).toBe(false);
+  });
+
+  test('skips when not dirty, cannot write, or already saving', () => {
+    expect(shouldScheduleFileAutosave({ ...ready, isDirty: false })).toBe(false);
+    expect(shouldScheduleFileAutosave({ ...ready, canWrite: false })).toBe(false);
+    expect(shouldScheduleFileAutosave({ ...ready, isSaving: true })).toBe(false);
+  });
+});
+
+describe('shouldAllowFileDraftSave', () => {
+  const ready = {
+    selectedFilePath: '/repo/a.txt',
+    loadedFilePath: '/repo/a.txt',
+    fileLoading: false,
+    isDirty: true,
+    draftContent: 'edited',
+    fileContent: 'original',
+    isNonEditableBinary: false,
+  };
+
+  test('allows save for loaded dirty text', () => {
+    expect(shouldAllowFileDraftSave(ready)).toBe(true);
+  });
+
+  test('refuses incomplete load or binary; clean draft is a successful no-op', () => {
+    expect(shouldAllowFileDraftSave({ ...ready, fileLoading: true })).toBe(false);
+    expect(shouldAllowFileDraftSave({ ...ready, loadedFilePath: null })).toBe(false);
+    expect(shouldAllowFileDraftSave({ ...ready, isNonEditableBinary: true })).toBe(false);
+    expect(shouldAllowFileDraftSave({ ...ready, isDirty: false })).toBe(true);
+  });
+});

packages/ui/src/lib/fileEditorAutosave.ts

@@ -0,0 +1,60 @@
+export type FileEditorAutosaveGate = {
+  autoSaveEnabled: boolean;
+  isDirty: boolean;
+  canWrite: boolean;
+  isSaving: boolean;
+  fileLoading: boolean;
+  selectedFilePath: string | null | undefined;
+  loadedFilePath: string | null;
+  /** True when the selected file must never be written as text (binary / non-editable). */
+  isNonEditableBinary: boolean;
+};
+
+/**
+ * Whether the FilesView autosave effect should schedule a debounced save.
+ * Incomplete loads and binary files must never trigger a write.
+ */
+export function shouldScheduleFileAutosave(gate: FileEditorAutosaveGate): boolean {
+  if (!gate.autoSaveEnabled || !gate.isDirty || !gate.canWrite || gate.isSaving) {
+    return false;
+  }
+  if (gate.fileLoading || gate.isNonEditableBinary) {
+    return false;
+  }
+  if (!gate.selectedFilePath || gate.loadedFilePath !== gate.selectedFilePath) {
+    return false;
+  }
+  return true;
+}
+
+export type FileEditorSaveDraftGate = {
+  selectedFilePath: string | null | undefined;
+  loadedFilePath: string | null;
+  fileLoading: boolean;
+  isDirty: boolean;
+  draftContent: string;
+  fileContent: string;
+  isNonEditableBinary: boolean;
+};
+
+/**
+ * Whether saveDraft may proceed.
+ * - Clean drafts return true ("nothing to save" is success) so callers like the
+ *   unsaved-changes dialog and Ctrl+S do not treat a no-op as failure.
+ * - Incomplete loads and binary targets return false (refused).
+ */
+export function shouldAllowFileDraftSave(gate: FileEditorSaveDraftGate): boolean {
+  if (!gate.selectedFilePath) {
+    return false;
+  }
+  if (!gate.isDirty) {
+    return true;
+  }
+  if (gate.fileLoading || gate.loadedFilePath !== gate.selectedFilePath || gate.isNonEditableBinary) {
+    return false;
+  }
+  if (gate.draftContent === '' && gate.fileContent !== '' && gate.loadedFilePath !== gate.selectedFilePath) {
+    return false;
+  }
+  return true;
+}

packages/ui/src/lib/i18n/messages/en.settings.ts

@@ -1883,6 +1883,9 @@ export const settingsDict = {
   'settings.openchamber.visual.field.promptNavigatorEnabled': 'Prompt Navigator',
   'settings.openchamber.visual.field.expandedEditorToolbarAria': 'Always show editor toolbar',
   'settings.openchamber.visual.field.expandedEditorToolbar': 'Always show editor toolbar (docked under the file tabs)',
+  'settings.openchamber.visual.field.autoSaveEnabledAria': 'Auto-save files',
+  'settings.openchamber.visual.field.autoSaveEnabled': 'Auto-save files',
+  'settings.openchamber.visual.field.autoSaveEnabledInfo': 'Automatically save file edits after you stop typing. Disable to require manual save.',
   'settings.openchamber.visual.field.wideChatLayoutAria': 'Wide chat layout',
   'settings.openchamber.visual.field.wideChatLayout': 'Wide Chat Layout',
   'settings.openchamber.visual.field.codeBlockLineWrapAria': 'Wrap code block lines',

packages/ui/src/lib/i18n/messages/en.ts

@@ -1247,6 +1247,8 @@ export const dict = {
   'filesView.editor.showControlsAria': 'Show editor controls',
   'filesView.editor.controlsTitle': 'Editor controls',
   'filesView.editor.pickFileFromTree': 'Pick a file from the tree.',
+  'filesView.editor.cannotPreviewBinary': 'Cannot preview binary file',
+  'filesView.editor.binaryFileDescription': 'This file is binary and cannot be edited in OpenChamber. Download it to open with another app.',
   'filesView.state.loading': 'Loading...',
   'filesView.state.openingFileAtChange': 'Opening file at change...',
   'filesView.tree.search.placeholder': 'Search files...',

packages/ui/src/lib/i18n/messages/es.settings.ts

@@ -1850,6 +1850,9 @@ export const settingsDict = {
   "settings.openchamber.visual.field.promptNavigatorEnabled": "Navegador de prompts",
   "settings.openchamber.visual.field.expandedEditorToolbarAria": "Mostrar siempre la barra de herramientas del editor",
   "settings.openchamber.visual.field.expandedEditorToolbar": "Mostrar siempre la barra de herramientas del editor (anclada bajo las pestañas)",
+  "settings.openchamber.visual.field.autoSaveEnabledAria": "Guardado automático de archivos",
+  "settings.openchamber.visual.field.autoSaveEnabled": "Guardado automático de archivos",
+  "settings.openchamber.visual.field.autoSaveEnabledInfo": "Guarda automáticamente las ediciones del archivo después de dejar de escribir. Desactívalo para exigir un guardado manual.",
   "settings.openchamber.visual.field.wideChatLayoutAria": "Diseño de chat ancho",
   "settings.openchamber.visual.field.wideChatLayout": "Diseño de chat ancho",
   "settings.openchamber.visual.field.showSplitAssistantMessageActionsAria": "Acciones en línea del asistente",

packages/ui/src/lib/i18n/messages/es.ts

@@ -1213,6 +1213,8 @@ export const dict: Record<I18nKey, string> = {
   "filesView.editor.showControlsAria": "Mostrar controles del editor",
   "filesView.editor.controlsTitle": "Controles del editor",
   "filesView.editor.pickFileFromTree": "Selecciona un archivo del árbol.",
+  "filesView.editor.cannotPreviewBinary": "No se puede previsualizar el archivo binario",
+  "filesView.editor.binaryFileDescription": "Este archivo es binario y no se puede editar en OpenChamber. Descárgalo para abrirlo con otra aplicación.",
   "filesView.state.loading": "Cargando...",
   "filesView.state.openingFileAtChange": "Abriendo archivo en cambio...",
   "filesView.tree.search.placeholder": "Buscar archivos...",

packages/ui/src/lib/i18n/messages/fr.settings.ts

@@ -1755,6 +1755,9 @@ export const settingsDict = {
   'settings.openchamber.visual.field.promptNavigatorEnabled': 'Navigateur de prompts',
   'settings.openchamber.visual.field.expandedEditorToolbarAria': 'Toujours afficher la barre d’outils de l’éditeur',
   'settings.openchamber.visual.field.expandedEditorToolbar': 'Toujours afficher la barre d’outils de l’éditeur (ancrée sous les onglets de fichiers)',
+  'settings.openchamber.visual.field.autoSaveEnabledAria': 'Enregistrement automatique des fichiers',
+  'settings.openchamber.visual.field.autoSaveEnabled': 'Enregistrement automatique des fichiers',
+  'settings.openchamber.visual.field.autoSaveEnabledInfo': 'Enregistre automatiquement les modifications après l’arrêt de la saisie. Désactivez pour exiger un enregistrement manuel.',
   'settings.openchamber.visual.field.wideChatLayoutAria': 'Large disposition de discussion',
   'settings.openchamber.visual.field.wideChatLayout': 'Disposition de discussion large',
   'settings.openchamber.visual.field.showSplitAssistantMessageActionsAria': 'Actions intégrées de l\'assistant',

packages/ui/src/lib/i18n/messages/fr.ts

@@ -1075,6 +1075,8 @@ export const dict = {
   'filesView.editor.showControlsAria': 'Afficher les contrôles de l\'éditeur',
   'filesView.editor.controlsTitle': 'Contrôles de l\'éditeur',
   'filesView.editor.pickFileFromTree': 'Choisissez un fichier dans l\'arborescence.',
+  'filesView.editor.cannotPreviewBinary': 'Impossible de prévisualiser le fichier binaire',
+  'filesView.editor.binaryFileDescription': 'Ce fichier est binaire et ne peut pas être modifié dans OpenChamber. Téléchargez-le pour l’ouvrir avec une autre application.',
   'filesView.state.loading': 'Chargement...',
   'filesView.state.openingFileAtChange': 'Ouverture du fichier lors du changement...',
   'filesView.tree.search.placeholder': 'Rechercher des fichiers...',

packages/ui/src/lib/i18n/messages/ja.settings.ts

@@ -1883,6 +1883,9 @@ export const settingsDict = {
   'settings.openchamber.visual.field.promptNavigatorEnabled': 'プロンプトナビゲーター',
   'settings.openchamber.visual.field.expandedEditorToolbarAria': 'エディターツールバーを常に表示',
   'settings.openchamber.visual.field.expandedEditorToolbar': 'エディターツールバーを常に表示（ファイルタブの下にドッキング）',
+  'settings.openchamber.visual.field.autoSaveEnabledAria': 'ファイルの自動保存',
+  'settings.openchamber.visual.field.autoSaveEnabled': 'ファイルの自動保存',
+  'settings.openchamber.visual.field.autoSaveEnabledInfo': '入力を止めた後にファイルの編集内容を自動保存します。無効にすると手動保存が必要になります。',
   'settings.openchamber.visual.field.wideChatLayoutAria': 'ワイドチャットレイアウト',
   'settings.openchamber.visual.field.wideChatLayout': 'ワイドチャットレイアウト',
   'settings.openchamber.visual.field.showSplitAssistantMessageActionsAria': 'インラインアシスタントアクション',

packages/ui/src/lib/i18n/messages/ja.ts

@@ -1243,6 +1243,8 @@ export const dict: Record<I18nKey, string> = {
   'filesView.editor.showControlsAria': 'エディターコントロールを表示',
   'filesView.editor.controlsTitle': 'エディターコントロール',
   'filesView.editor.pickFileFromTree': 'ツリーからファイルを選択してください。',
+  'filesView.editor.cannotPreviewBinary': 'バイナリファイルはプレビューできません',
+  'filesView.editor.binaryFileDescription': 'このファイルはバイナリのため、OpenChamberでは編集できません。別のアプリで開くにはダウンロードしてください。',
   'filesView.state.loading': '読み込み中...',
   'filesView.state.openingFileAtChange': '変更箇所のファイルを開いています...',
   'filesView.tree.search.placeholder': 'ファイルを検索...',

packages/ui/src/lib/i18n/messages/ko.settings.ts

@@ -1850,6 +1850,9 @@ export const settingsDict = {
   'settings.openchamber.visual.field.promptNavigatorEnabled': '프롬프트 탐색기',
   'settings.openchamber.visual.field.expandedEditorToolbarAria': 'Always show editor toolbar',
   'settings.openchamber.visual.field.expandedEditorToolbar': 'Always show editor toolbar (docked under the file tabs)',
+  'settings.openchamber.visual.field.autoSaveEnabledAria': '파일 자동 저장',
+  'settings.openchamber.visual.field.autoSaveEnabled': '파일 자동 저장',
+  'settings.openchamber.visual.field.autoSaveEnabledInfo': '입력을 멈춘 후 파일 편집 내용을 자동으로 저장합니다. 끄면 수동으로 저장해야 합니다.',
   'settings.openchamber.visual.field.wideChatLayoutAria': '넓은 채팅 레이아웃',
   'settings.openchamber.visual.field.wideChatLayout': '넓은 채팅 레이아웃',
   'settings.openchamber.visual.field.showSplitAssistantMessageActionsAria': '인라인 어시스턴트 작업',

packages/ui/src/lib/i18n/messages/ko.ts

@@ -1250,6 +1250,8 @@ export const dict: Record<I18nKey, string> = {
   'filesView.editor.showControlsAria': '편집기 컨트롤 표시',
   'filesView.editor.controlsTitle': '편집기 컨트롤',
   'filesView.editor.pickFileFromTree': '트리에서 파일을 선택하세요.',
+  'filesView.editor.cannotPreviewBinary': '바이너리 파일을 미리볼 수 없음',
+  'filesView.editor.binaryFileDescription': '이 파일은 바이너리이므로 OpenChamber에서 편집할 수 없습니다. 다른 앱으로 열려면 다운로드하세요.',
   'filesView.state.loading': '로드 중…',
   'filesView.state.openingFileAtChange': '변경 위치에서 파일 여는 중…',
   'filesView.tree.search.placeholder': '파일 검색…',

packages/ui/src/lib/i18n/messages/pl.settings.ts

@@ -1090,6 +1090,9 @@ export const settingsDict = {
   'settings.openchamber.visual.field.promptNavigatorEnabled': 'Nawigator promptów',
   'settings.openchamber.visual.field.expandedEditorToolbarAria': 'Always show editor toolbar',
   'settings.openchamber.visual.field.expandedEditorToolbar': 'Always show editor toolbar (docked under the file tabs)',
+  'settings.openchamber.visual.field.autoSaveEnabledAria': 'Autozapis plików',
+  'settings.openchamber.visual.field.autoSaveEnabled': 'Autozapis plików',
+  'settings.openchamber.visual.field.autoSaveEnabledInfo': 'Automatycznie zapisuje edycje pliku po zatrzymaniu pisania. Wyłącz, aby wymagać ręcznego zapisu.',
   'settings.openchamber.visual.field.terminalFontSize': 'Rozmiar czcionki terminala',
   'settings.openchamber.visual.field.terminalShell': 'Powłoka terminala',
   'settings.openchamber.visual.field.terminalShellAria': 'Wybierz powłokę terminala',

packages/ui/src/lib/i18n/messages/pl.ts

@@ -1728,6 +1728,8 @@ export const dict: Record<I18nKey, string> = {
   'filesView.editor.openFilesAria': 'Otwarte pliki',
   'filesView.editor.openInDesktopApp': 'Otwórz w aplikacji desktopowej',
   'filesView.editor.pickFileFromTree': 'Wybierz plik z drzewa.',
+  'filesView.editor.cannotPreviewBinary': 'Nie można podglądać pliku binarnego',
+  'filesView.editor.binaryFileDescription': 'Ten plik jest binarny i nie można go edytować w OpenChamber. Pobierz go, aby otworzyć w innej aplikacji.',
   'filesView.editor.refreshApps': 'Odśwież aplikacje',
   'filesView.editor.saveAria': 'Zapisz ({shortcut})',
   'filesView.editor.saveFile': 'Zapisz plik',

packages/ui/src/lib/i18n/messages/pt-BR.settings.ts

@@ -1850,6 +1850,9 @@ export const settingsDict = {
   "settings.openchamber.visual.field.promptNavigatorEnabled": "Navegador de prompts",
   "settings.openchamber.visual.field.expandedEditorToolbarAria": "Mostrar sempre a barra de ferramentas do editor",
   "settings.openchamber.visual.field.expandedEditorToolbar": "Mostrar sempre a barra de ferramentas do editor (ancorada sob as abas)",
+  "settings.openchamber.visual.field.autoSaveEnabledAria": "Salvamento automático de arquivos",
+  "settings.openchamber.visual.field.autoSaveEnabled": "Salvamento automático de arquivos",
+  "settings.openchamber.visual.field.autoSaveEnabledInfo": "Salva automaticamente as edições do arquivo depois que você parar de digitar. Desative para exigir salvamento manual.",
   "settings.openchamber.visual.field.wideChatLayoutAria": "Layout de chat amplo",
   "settings.openchamber.visual.field.wideChatLayout": "Layout de chat amplo",
   "settings.openchamber.visual.field.showSplitAssistantMessageActionsAria": "Ações inline do assistente",

packages/ui/src/lib/i18n/messages/pt-BR.ts

@@ -1213,6 +1213,8 @@ export const dict: Record<I18nKey, string> = {
   "filesView.editor.showControlsAria": "Mostrar controles do editor",
   "filesView.editor.controlsTitle": "Controles do editor",
   "filesView.editor.pickFileFromTree": "Selecione um arquivo na árvore.",
+  "filesView.editor.cannotPreviewBinary": "Não é possível pré-visualizar o arquivo binário",
+  "filesView.editor.binaryFileDescription": "Este arquivo é binário e não pode ser editado no OpenChamber. Baixe-o para abrir em outro aplicativo.",
   "filesView.state.loading": "Carregando...",
   "filesView.state.openingFileAtChange": "Abrindo arquivo na alteração...",
   "filesView.tree.search.placeholder": "Pesquisar arquivos...",

packages/ui/src/lib/i18n/messages/uk.settings.ts

@@ -1850,6 +1850,9 @@ export const settingsDict = {
   "settings.openchamber.visual.field.promptNavigatorEnabled": "Навігатор промптів",
   "settings.openchamber.visual.field.expandedEditorToolbarAria": "Завжди показувати панель інструментів редактора",
   "settings.openchamber.visual.field.expandedEditorToolbar": "Завжди показувати панель інструментів редактора (закріплена під вкладками)",
+  "settings.openchamber.visual.field.autoSaveEnabledAria": "Автозбереження файлів",
+  "settings.openchamber.visual.field.autoSaveEnabled": "Автозбереження файлів",
+  "settings.openchamber.visual.field.autoSaveEnabledInfo": "Автоматично зберігати зміни у файлі після того, як ви припините друкувати. Вимкніть, щоб зберігати лише вручну.",
   "settings.openchamber.visual.field.wideChatLayoutAria": "Широкий макет чату",
   "settings.openchamber.visual.field.wideChatLayout": "Широкий макет чату",
   "settings.openchamber.visual.field.showSplitAssistantMessageActionsAria": "Вбудовані дії асистента",

packages/ui/src/lib/i18n/messages/uk.ts

@@ -1213,6 +1213,8 @@ export const dict: Record<I18nKey, string> = {
   "filesView.editor.showControlsAria": "Показати елементи керування редактора",
   "filesView.editor.controlsTitle": "Елементи керування редактора",
   "filesView.editor.pickFileFromTree": "Вибрати файл із дерева.",
+  "filesView.editor.cannotPreviewBinary": "Неможливо попередньо переглянути бінарний файл",
+  "filesView.editor.binaryFileDescription": "Цей файл є бінарним і його не можна редагувати в OpenChamber. Завантажте його, щоб відкрити в іншій програмі.",
   "filesView.state.loading": "Завантаження...",
   "filesView.state.openingFileAtChange": "Відкриття файлу на зміні...",
   "filesView.tree.search.placeholder": "Пошук файлів...",

packages/ui/src/lib/i18n/messages/zh-CN.settings.ts

@@ -1850,6 +1850,9 @@ export const settingsDict = {
   'settings.openchamber.visual.field.promptNavigatorEnabled': '提示词导航',
   'settings.openchamber.visual.field.expandedEditorToolbarAria': 'Always show editor toolbar',
   'settings.openchamber.visual.field.expandedEditorToolbar': 'Always show editor toolbar (docked under the file tabs)',
+  'settings.openchamber.visual.field.autoSaveEnabledAria': '自动保存文件',
+  'settings.openchamber.visual.field.autoSaveEnabled': '自动保存文件',
+  'settings.openchamber.visual.field.autoSaveEnabledInfo': '停止输入后自动保存文件编辑内容。关闭后需手动保存。',
   'settings.openchamber.visual.field.wideChatLayoutAria': '宽聊天布局',
   'settings.openchamber.visual.field.wideChatLayout': '宽聊天布局',
   'settings.openchamber.visual.field.showSplitAssistantMessageActionsAria': '内联助手操作',

packages/ui/src/lib/i18n/messages/zh-CN.ts

@@ -1213,6 +1213,8 @@ export const dict: Record<I18nKey, string> = {
   'filesView.editor.showControlsAria': '显示编辑器控制项',
   'filesView.editor.controlsTitle': '编辑器控制项',
   'filesView.editor.pickFileFromTree': '请从文件树中选择一个文件。',
+  'filesView.editor.cannotPreviewBinary': '无法预览二进制文件',
+  'filesView.editor.binaryFileDescription': '此文件为二进制文件，无法在 OpenChamber 中编辑。请下载后使用其他应用打开。',
   'filesView.state.loading': '加载中...',
   'filesView.state.openingFileAtChange': '正在打开变更处的文件...',
   'filesView.tree.search.placeholder': '搜索文件...',

packages/ui/src/lib/i18n/messages/zh-TW.settings.ts

@@ -1756,6 +1756,9 @@
   'settings.openchamber.visual.field.promptNavigatorEnabled': '提示詞導覽',
   'settings.openchamber.visual.field.expandedEditorToolbarAria': 'Always show editor toolbar',
   'settings.openchamber.visual.field.expandedEditorToolbar': 'Always show editor toolbar (docked under the file tabs)',
+  'settings.openchamber.visual.field.autoSaveEnabledAria': '自動儲存檔案',
+  'settings.openchamber.visual.field.autoSaveEnabled': '自動儲存檔案',
+  'settings.openchamber.visual.field.autoSaveEnabledInfo': '停止輸入後自動儲存檔案編輯內容。關閉後需手動儲存。',
   'settings.openchamber.visual.field.wideChatLayoutAria': '寬聊天佈局',
   'settings.openchamber.visual.field.wideChatLayout': '寬聊天佈局',
   'settings.openchamber.visual.field.showSplitAssistantMessageActionsAria': '行內助理操作',

packages/ui/src/lib/i18n/messages/zh-TW.ts

@@ -1224,6 +1224,8 @@ export const dict: Record<I18nKey, string> = {
   'filesView.editor.showControlsAria': '顯示編輯器控制項',
   'filesView.editor.controlsTitle': '編輯器控制項',
   'filesView.editor.pickFileFromTree': '請從檔案樹中選擇一個檔案。',
+  'filesView.editor.cannotPreviewBinary': '無法預覽二進位檔案',
+  'filesView.editor.binaryFileDescription': '此檔案為二進位檔案，無法在 OpenChamber 中編輯。請下載後使用其他應用程式開啟。',
   'filesView.state.loading': '載入中...',
   'filesView.state.openingFileAtChange': '正在開啟變更處的檔案...',
   'filesView.tree.search.placeholder': '搜尋檔案...',

packages/ui/src/lib/persistence.test.ts

@@ -497,4 +497,74 @@ describe('updateDesktopSettings', () => {
     expect(saveCalls.some((changes) => changes.terminalShell === 'zsh')).toBe(true);
     expect(saveCalls.some((changes) => changes.terminalLoginShells?.includes('zsh'))).toBe(true);
   });
+
+  test('applies persisted autoSaveEnabled from server settings', async () => {
+    getWindow();
+    invalidateSettingsCache();
+    useUIStore.getState().setAutoSaveEnabled(true);
+    registerSettingsApi(async () => ({}), async () => ({
+      settings: { autoSaveEnabled: false, draftStartersCraftGoalAdded: true, draftStartersScheduleTaskAdded: true },
+      source: 'web',
+    }));
+
+    await syncDesktopSettings();
+
+    expect(useUIStore.getState().autoSaveEnabled).toBe(false);
+  });
+
+  test('autosaves autoSaveEnabled changes to shared settings', async () => {
+    getWindow();
+    useUIStore.getState().setAutoSaveEnabled(true);
+    const saveCalls: Array<Partial<SettingsPayload>> = [];
+    registerSettingsSave(async (changes) => {
+      saveCalls.push(changes);
+      return changes as SettingsPayload;
+    });
+    startAppearanceAutoSave();
+
+    useUIStore.getState().setAutoSaveEnabled(false);
+    await delay(500);
+
+    expect(saveCalls.some((changes) => changes.autoSaveEnabled === false)).toBe(true);
+  });
+
+  test('seeds omitted autoSaveEnabled from the hydrated client preference', async () => {
+    getWindow();
+    invalidateSettingsCache();
+    useUIStore.getState().setAutoSaveEnabled(false);
+    const saveCalls: Array<Partial<SettingsPayload>> = [];
+    registerSettingsApi(async (changes) => {
+      saveCalls.push(changes);
+      return { ...changes } as SettingsPayload;
+    }, async () => ({
+      settings: { draftStartersCraftGoalAdded: true, draftStartersScheduleTaskAdded: true },
+      source: 'web',
+    }));
+
+    await syncDesktopSettings();
+    await delay(500);
+
+    expect(useUIStore.getState().autoSaveEnabled).toBe(false);
+    expect(saveCalls.some((changes) => changes.autoSaveEnabled === false)).toBe(true);
+  });
+
+  test('seeds default autoSaveEnabled when omitted and client still has the default', async () => {
+    getWindow();
+    invalidateSettingsCache();
+    useUIStore.getState().setAutoSaveEnabled(true);
+    const saveCalls: Array<Partial<SettingsPayload>> = [];
+    registerSettingsApi(async (changes) => {
+      saveCalls.push(changes);
+      return { ...changes } as SettingsPayload;
+    }, async () => ({
+      settings: { draftStartersCraftGoalAdded: true, draftStartersScheduleTaskAdded: true },
+      source: 'web',
+    }));
+
+    await syncDesktopSettings();
+    await delay(500);
+
+    expect(useUIStore.getState().autoSaveEnabled).toBe(true);
+    expect(saveCalls.some((changes) => changes.autoSaveEnabled === true)).toBe(true);
+  });
 });

packages/ui/src/lib/persistence.ts

@@ -531,6 +531,7 @@ const materializeAuthoritativeUiSettings = (settings: DesktopSettings): DesktopS
     sessionGoalDefaultBudget: defaults.sessionGoalDefaultBudget,
     collapsibleThinkingBlocks: defaults.collapsibleThinkingBlocks,
     autoDeleteEnabled: defaults.autoDeleteEnabled,
+    autoSaveEnabled: defaults.autoSaveEnabled,
     autoDeleteAfterDays: defaults.autoDeleteAfterDays,
     sessionRetentionAction: defaults.sessionRetentionAction,
     followUpBehavior: DEFAULT_FOLLOW_UP_BEHAVIOR,
@@ -637,6 +638,9 @@ const applyDesktopUiPreferences = (settings: DesktopSettings) => {
   if (typeof settings.autoDeleteEnabled === 'boolean' && settings.autoDeleteEnabled !== store.autoDeleteEnabled) {
     store.setAutoDeleteEnabled(settings.autoDeleteEnabled);
   }
+  if (typeof settings.autoSaveEnabled === 'boolean' && settings.autoSaveEnabled !== store.autoSaveEnabled) {
+    store.setAutoSaveEnabled(settings.autoSaveEnabled);
+  }
   if (typeof settings.autoDeleteAfterDays === 'number' && Number.isFinite(settings.autoDeleteAfterDays)) {
     const normalized = Math.max(1, Math.min(365, settings.autoDeleteAfterDays));
     if (normalized !== store.autoDeleteAfterDays) {
@@ -1095,6 +1099,9 @@ const sanitizeWebSettings = (payload: unknown): DesktopSettings | null => {
   if (typeof candidate.autoDeleteEnabled === 'boolean') {
     result.autoDeleteEnabled = candidate.autoDeleteEnabled;
   }
+  if (typeof candidate.autoSaveEnabled === 'boolean') {
+    result.autoSaveEnabled = candidate.autoSaveEnabled;
+  }
   if (typeof candidate.autoDeleteAfterDays === 'number' && Number.isFinite(candidate.autoDeleteAfterDays)) {
     result.autoDeleteAfterDays = candidate.autoDeleteAfterDays;
   }
@@ -1737,6 +1744,12 @@ export const syncDesktopSettings = async (): Promise<void> => {
     if (!isSettingsRuntimeContextCurrent(context)) return;
     const shouldPersistCraftGoalMigration = settings.draftStartersCraftGoalAdded !== true
       || settings.draftStartersScheduleTaskAdded !== true;
+    // `autoSaveEnabled` is new to the settings backend. Until the server has a
+    // value, materialize would invent the client default (true) and overwrite a
+    // deliberate legacy "off" preference migrated from
+    // `openchamber:files:auto-save-enabled`. Prefer the hydrated store value and
+    // seed the backend once so later omitted→default authority is correct.
+    const shouldSeedAutoSaveEnabled = typeof settings.autoSaveEnabled !== 'boolean';
     const authoritativeSettings = materializeAuthoritativeUiSettings(settings);
     try {
       persistToLocalStorage(settings);
@@ -1745,6 +1758,9 @@ export const syncDesktopSettings = async (): Promise<void> => {
     }
     await waitForHydration();
     if (!isSettingsRuntimeContextCurrent(context)) return;
+    if (shouldSeedAutoSaveEnabled) {
+      authoritativeSettings.autoSaveEnabled = useUIStore.getState().autoSaveEnabled;
+    }
     if (settings.draftStarters === undefined) {
       useUIStore.setState({ globalDraftStarters: null });
     }
@@ -1753,12 +1769,19 @@ export const syncDesktopSettings = async (): Promise<void> => {
     } catch (error) {
       console.warn('applyDesktopUiPreferences failed:', error);
     }
+    const migrationPatch: Partial<DesktopSettings> = {};
     if (shouldPersistCraftGoalMigration) {
-      await updateDesktopSettings({
+      if (authoritativeSettings.draftStarters) {
-        ...(authoritativeSettings.draftStarters ? { draftStarters: authoritativeSettings.draftStarters } : {}),
+        migrationPatch.draftStarters = authoritativeSettings.draftStarters;
-        draftStartersCraftGoalAdded: true,
+      }
-        draftStartersScheduleTaskAdded: true,
+      migrationPatch.draftStartersCraftGoalAdded = true;
-      });
+      migrationPatch.draftStartersScheduleTaskAdded = true;
+    }
+    if (shouldSeedAutoSaveEnabled) {
+      migrationPatch.autoSaveEnabled = authoritativeSettings.autoSaveEnabled;
+    }
+    if (Object.keys(migrationPatch).length > 0) {
+      await updateDesktopSettings(migrationPatch);
       if (!isSettingsRuntimeContextCurrent(context)) return;
     }
 

packages/ui/src/lib/settings/search.ts

@@ -147,6 +147,13 @@ const SETTINGS_SEARCH_ITEMS: readonly SettingsSearchItem[] = [
     // Only the mobile composer applies this offset (ChatInput gates on isMobile).
     isAvailable: (ctx) => ctx.isMobile,
   },
+  {
+    id: 'appearance.auto-save-enabled',
+    page: 'general',
+    titleKey: 'settings.openchamber.visual.field.autoSaveEnabled',
+    descriptionKey: 'settings.openchamber.visual.field.autoSaveEnabledInfo',
+    keywords: ['editor', 'autosave', 'auto-save', 'files', 'save'],
+  },
   {
     id: 'appearance.expanded-editor-toolbar',
     page: 'general',

packages/ui/src/lib/toolHelpers.binary.test.ts

@@ -0,0 +1,44 @@
+import { describe, expect, test } from 'bun:test';
+
+import {
+  getFileExtension,
+  isBinaryFile,
+  isImageFile,
+  isPdfFile,
+  isSvgFile,
+  looksLikeBinaryText,
+} from './toolHelpers';
+
+describe('binary file helpers', () => {
+  test('classifies common binary extensions', () => {
+    expect(isBinaryFile('/repo/docs/report.pdf')).toBe(true);
+    expect(isBinaryFile('/repo/sheet.XLSX')).toBe(true);
+    expect(isBinaryFile('archive.zip')).toBe(true);
+    expect(isBinaryFile('photo.png')).toBe(true);
+    expect(isBinaryFile('notes.docx')).toBe(true);
+    expect(isPdfFile('report.pdf')).toBe(true);
+    expect(isImageFile('photo.png')).toBe(true);
+  });
+
+  test('keeps text and SVG editable', () => {
+    expect(isBinaryFile('/repo/README.md')).toBe(false);
+    expect(isBinaryFile('/repo/src/main.ts')).toBe(false);
+    expect(isBinaryFile('/repo/icon.svg')).toBe(false);
+    expect(isSvgFile('/repo/icon.svg')).toBe(true);
+    expect(isBinaryFile('/repo/.env')).toBe(false);
+  });
+
+  test('getFileExtension ignores leading dots and path separators', () => {
+    expect(getFileExtension('/a/b/c.PDF')).toBe('pdf');
+    expect(getFileExtension('.gitignore')).toBe('');
+    expect(getFileExtension('Makefile')).toBe('');
+  });
+
+  test('looksLikeBinaryText detects nulls, PDF, ZIP, and replacement-heavy content', () => {
+    expect(looksLikeBinaryText('hello\0world')).toBe(true);
+    expect(looksLikeBinaryText('%PDF-1.7\nstream\n...')).toBe(true);
+    expect(looksLikeBinaryText(`PK\u0003\u0004${'x'.repeat(20)}`)).toBe(true);
+    expect(looksLikeBinaryText(`${'\uFFFD'.repeat(40)}${'a'.repeat(40)}`)).toBe(true);
+    expect(looksLikeBinaryText('plain text file\nwith newlines\n')).toBe(false);
+  });
+});

packages/ui/src/lib/toolHelpers.ts

@@ -705,6 +705,84 @@ export function isPdfFile(filePath: string): boolean {
   return ext === 'pdf';
 }
 
+export function isSvgFile(filePath: string): boolean {
+  return filePath.toLowerCase().endsWith('.svg');
+}
+
+/** Known non-text extensions that must not be opened or saved as UTF-8 text. */
+const BINARY_FILE_EXTENSIONS = new Set([
+  // Documents / office
+  'pdf', 'doc', 'docx', 'xls', 'xlsx', 'ppt', 'pptx', 'odt', 'ods', 'odp',
+  // Archives / packages
+  'zip', 'rar', '7z', 'gz', 'tgz', 'tar', 'bz2', 'xz', 'jar', 'war', 'apk', 'dmg', 'iso',
+  'deb', 'rpm', 'msi',
+  // Images (svg is text and is excluded via isSvgFile)
+  ...IMAGE_EXTENSIONS.filter((ext) => ext !== 'svg'),
+  // Audio / video
+  'mp3', 'mp4', 'm4a', 'aac', 'flac', 'ogg', 'wav', 'wma', 'avi', 'mov', 'mkv', 'webm', 'wmv',
+  // Fonts
+  'ttf', 'otf', 'woff', 'woff2', 'eot',
+  // Native / bytecode
+  'exe', 'dll', 'so', 'dylib', 'bin', 'class', 'o', 'a', 'lib', 'wasm', 'node',
+  // Databases / locks / misc binary
+  'sqlite', 'sqlite3', 'db', 'dat', 'parquet', 'feather', 'pickle', 'pyc', 'pyo', 'lockb',
+]);
+
+export function getFileExtension(filePath: string): string {
+  const base = filePath.split(/[/\\]/).pop() ?? filePath;
+  const dot = base.lastIndexOf('.');
+  if (dot <= 0 || dot === base.length - 1) {
+    return '';
+  }
+  return base.slice(dot + 1).toLowerCase();
+}
+
+/** True for known binary extensions (including images/PDF). SVG is not binary. */
+export function isBinaryFile(filePath: string): boolean {
+  if (isSvgFile(filePath)) {
+    return false;
+  }
+  const ext = getFileExtension(filePath);
+  return BINARY_FILE_EXTENSIONS.has(ext);
+}
+
+/**
+ * Heuristic for UTF-8 text that is actually binary (or was lossily decoded).
+ * Used as defense-in-depth when extension checks miss a binary file.
+ */
+export function looksLikeBinaryText(content: string): boolean {
+  if (!content) {
+    return false;
+  }
+
+  const sample = content.length > 8192 ? content.slice(0, 8192) : content;
+  if (sample.includes('\0')) {
+    return true;
+  }
+  if (sample.startsWith('%PDF')) {
+    return true;
+  }
+  // ZIP-based formats (docx/xlsx/pptx/jar/apk…) and raw ZIP.
+  if (sample.startsWith('PK\u0003\u0004') || sample.startsWith('PK\u0005\u0006') || sample.startsWith('PK\u0007\u0008')) {
+    return true;
+  }
+
+  let suspicious = 0;
+  for (let index = 0; index < sample.length; index += 1) {
+    const code = sample.charCodeAt(index);
+    if (code === 0xFFFD) {
+      suspicious += 1;
+      continue;
+    }
+    // C0 controls excluding common whitespace (TAB/LF/VT/FF/CR).
+    if (code < 9 || (code > 13 && code < 32) || code === 127) {
+      suspicious += 1;
+    }
+  }
+
+  return sample.length > 0 && suspicious / sample.length > 0.1;
+}
+
 export function getImageMimeType(filePath: string): string {
   const ext = filePath.split('.').pop()?.toLowerCase();
   const mimeMap: Record<string, string> = {

packages/ui/src/stores/useUIStore.ts

@@ -621,6 +621,8 @@ interface UIStore {
   activityRenderMode: ActivityRenderMode;
   showDeletionDialog: boolean;
   autoDeleteEnabled: boolean;
+  /** Global file-editor autosave. Default true for backward compatibility. */
+  autoSaveEnabled: boolean;
   autoDeleteAfterDays: number;
   sessionRetentionAction: SessionRetentionAction;
   autoDeleteLastRunAt: number | null;
@@ -784,6 +786,7 @@ interface UIStore {
   setActivityRenderMode: (value: ActivityRenderMode) => void;
   setShowDeletionDialog: (value: boolean) => void;
   setAutoDeleteEnabled: (value: boolean) => void;
+  setAutoSaveEnabled: (value: boolean) => void;
   setAutoDeleteAfterDays: (days: number) => void;
   setSessionRetentionAction: (value: SessionRetentionAction) => void;
   setAutoDeleteLastRunAt: (timestamp: number | null) => void;
@@ -941,6 +944,7 @@ export const useUIStore = create<UIStore>()(
         activityRenderMode: 'summary',
         showDeletionDialog: true,
         autoDeleteEnabled: false,
+        autoSaveEnabled: true,
         autoDeleteAfterDays: 30,
         sessionRetentionAction: 'archive',
         autoDeleteLastRunAt: null,
@@ -1682,6 +1686,10 @@ export const useUIStore = create<UIStore>()(
           set({ autoDeleteEnabled: value });
         },
 
+        setAutoSaveEnabled: (value) => {
+          set({ autoSaveEnabled: value });
+        },
+
         setAutoDeleteAfterDays: (days) => {
           const clampedDays = Math.max(1, Math.min(365, days));
           set({ autoDeleteAfterDays: clampedDays });
@@ -2254,13 +2262,32 @@ export const useUIStore = create<UIStore>()(
       {
         name: 'ui-store',
         storage: createDeferredSafeJSONStorage(),
-        version: 12,
+        version: 13,
         migrate: (persistedState, version) => {
           if (!persistedState || typeof persistedState !== 'object') {
             return persistedState;
           }
           const state = persistedState as Record<string, unknown>;
 
+          // v12 -> v13: promote FilesView localStorage autosave toggle into the store.
+          if (version < 13) {
+            if (typeof state.autoSaveEnabled !== 'boolean') {
+              let legacyEnabled = true;
+              try {
+                if (typeof localStorage !== 'undefined') {
+                  const legacy = localStorage.getItem('openchamber:files:auto-save-enabled');
+                  if (legacy !== null) {
+                    legacyEnabled = legacy !== 'false';
+                    localStorage.removeItem('openchamber:files:auto-save-enabled');
+                  }
+                }
+              } catch {
+                legacyEnabled = true;
+              }
+              state.autoSaveEnabled = legacyEnabled;
+            }
+          }
+
           // v11 -> v12: drop legacy window-controls "auto" (always meant right).
           if (version < 12) {
             if (state.desktopWindowControlsPosition === 'auto' || state.desktopWindowControlsPosition == null) {
@@ -2360,6 +2387,10 @@ export const useUIStore = create<UIStore>()(
 
           state.fileEditorKeymap = normalizeFileEditorKeymap(state.fileEditorKeymap);
 
+          if (typeof state.autoSaveEnabled !== 'boolean') {
+            state.autoSaveEnabled = true;
+          }
+
           state.contextRailOrder = Array.isArray(state.contextRailOrder)
             ? (state.contextRailOrder as unknown[]).filter((id): id is string => typeof id === 'string' && id.trim() !== '')
             : [];
@@ -2396,6 +2427,7 @@ export const useUIStore = create<UIStore>()(
           activityRenderMode: state.activityRenderMode,
           showDeletionDialog: state.showDeletionDialog,
           autoDeleteEnabled: state.autoDeleteEnabled,
+          autoSaveEnabled: state.autoSaveEnabled,
           autoDeleteAfterDays: state.autoDeleteAfterDays,
           sessionRetentionAction: state.sessionRetentionAction,
           autoDeleteLastRunAt: state.autoDeleteLastRunAt,