fix: guard all window.markupr accesses to prevent crash when preload fails

On fresh installs or after upgrading from older versions, the Electron
preload script can fail to load, leaving window.markupr undefined. This
caused an immediate crash: "Cannot read properties of undefined (reading
'whisper')" because RecordingContext, UIContext, and ModelDownloadDialog
all access window.markupr synchronously on mount without null checks.

Added optional chaining guards to all critical mount-time useEffects so
the app degrades gracefully instead of crashing.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: eddiesanjuan

src/renderer/components/ModelDownloadDialog.tsx

@@ -78,6 +78,7 @@ function useModelDownload(): UseModelDownloadResult {
   const [error, setError] = useState<string | null>(null);
 
   useEffect(() => {
+    if (!window.markupr?.whisper) return;
     // Subscribe to download events
     const unsubProgress = window.markupr.whisper.onDownloadProgress((p) => {
       setProgress(p);
@@ -105,15 +106,15 @@ function useModelDownload(): UseModelDownloadResult {
     setError(null);
     setProgress(null);
 
-    const result = await window.markupr.whisper.downloadModel(model);
-    if (!result.success && result.error) {
+    const result = await window.markupr?.whisper?.downloadModel(model);
+    if (!result?.success && result?.error) {
       setError(result.error);
       setIsDownloading(false);
     }
   }, []);
 
   const cancelDownload = useCallback((model: string) => {
-    window.markupr.whisper.cancelDownload(model);
+    window.markupr?.whisper?.cancelDownload(model);
     setIsDownloading(false);
     setProgress(null);
   }, []);
@@ -145,6 +146,7 @@ export const ModelDownloadDialog: React.FC<ModelDownloadDialogProps> = ({
 
   // Load available models on mount
   useEffect(() => {
+    if (!window.markupr?.whisper) return;
     const loadModels = async () => {
       const availableModels = await window.markupr.whisper.getAvailableModels();
       setModels(availableModels);
@@ -163,6 +165,7 @@ export const ModelDownloadDialog: React.FC<ModelDownloadDialogProps> = ({
 
   // Listen for download complete to transition state
   useEffect(() => {
+    if (!window.markupr?.whisper) return;
     const unsubComplete = window.markupr.whisper.onDownloadComplete(() => {
       setState('complete');
     });
@@ -494,6 +497,10 @@ export function useModelCheck(): ModelCheckResult {
 
     const checkModel = async () => {
       try {
+        if (!window.markupr?.whisper) {
+          setNeedsDownload(true);
+          return;
+        }
         // Check if we have any transcription capability (OpenAI or Whisper)
         const hasCapability = await withTimeout(
           window.markupr.whisper.hasTranscriptionCapability(),

src/renderer/contexts/RecordingContext.tsx

@@ -173,6 +173,7 @@ export const RecordingProvider: React.FC<{ children: React.ReactNode }> = ({ chi
   // Transcription capability check
   // ---------------------------------------------------------------------------
   useEffect(() => {
+    if (!window.markupr?.whisper) return;
     window.markupr.whisper
       .hasTranscriptionCapability()
       .then((ready) => setHasTranscriptionCapability(ready))
@@ -289,6 +290,7 @@ export const RecordingProvider: React.FC<{ children: React.ReactNode }> = ({ chi
   // Session IPC listeners
   // ---------------------------------------------------------------------------
   useEffect(() => {
+    if (!window.markupr?.session) return;
     let mounted = true;
     const recorder = screenRecorderRef.current;
 
@@ -425,6 +427,7 @@ export const RecordingProvider: React.FC<{ children: React.ReactNode }> = ({ chi
   // Audio level + voice activity listeners
   // ---------------------------------------------------------------------------
   useEffect(() => {
+    if (!window.markupr?.audio) return;
     const unsubLevel = window.markupr.audio.onLevel((level) => {
       setAudioLevel(level);
     });
@@ -490,8 +493,8 @@ export const RecordingProvider: React.FC<{ children: React.ReactNode }> = ({ chi
       if (!result.success) {
         setState('error');
         setErrorMessage(result.error || 'Unable to start session.');
-        window.markupr.whisper
-          .hasTranscriptionCapability()
+        window.markupr?.whisper
+          ?.hasTranscriptionCapability()
           .then((ready) => setHasTranscriptionCapability(ready))
           .catch(() => {});
       } else {

src/renderer/contexts/UIContext.tsx

@@ -109,6 +109,7 @@ export const UIProvider: React.FC<{ children: React.ReactNode }> = ({ children }
   const [hasRequiredByokKeys, setHasRequiredByokKeys] = useState<boolean | null>(null);
 
   useEffect(() => {
+    if (!window.markupr?.settings) return;
     let mounted = true;
     const loadInitialSettings = async () => {
       try {
@@ -140,7 +141,7 @@ export const UIProvider: React.FC<{ children: React.ReactNode }> = ({ children }
   // Navigation event listeners (from main process menu/tray)
   // ---------------------------------------------------------------------------
   useEffect(() => {
-    const nav = window.markupr.navigation;
+    const nav = window.markupr?.navigation;
     if (!nav) return;
 
     const unsubSettings = nav.onShowSettings(() => setCurrentView('settings'));
@@ -172,6 +173,7 @@ export const UIProvider: React.FC<{ children: React.ReactNode }> = ({ children }
   // Popover resize on state/view change
   // ---------------------------------------------------------------------------
   useEffect(() => {
+    if (!window.markupr?.popover) return;
     if (currentView !== 'main') {
       const { width, height } = mapOverlaySize(currentView);
       window.markupr.popover.resize(width, height).catch(() => {});
@@ -248,9 +250,9 @@ export const UIProvider: React.FC<{ children: React.ReactNode }> = ({ children }
 
   const handleOnboardingComplete = useCallback(() => {
     setShowOnboarding(false);
-    window.markupr.setSettings({ hasCompletedOnboarding: true }).catch(() => {});
-    window.markupr.whisper
-      .hasTranscriptionCapability()
+    window.markupr?.setSettings({ hasCompletedOnboarding: true }).catch(() => {});
+    window.markupr?.whisper
+      ?.hasTranscriptionCapability()
       .then(() => {})
       .catch(() => {});
   }, []);