Correct what the volume keys do behind a modal

App.tsx

@@ -1544,9 +1544,9 @@ export default function App() {
     return () => sub.remove();
   }, []);
   // Only the camera screen claims the keys; everywhere else (the library)
-  // they stay volume keys.
-  // ponytail: keyed off the mode alone, so a press behind a modal still
-  // takes a frame - add the overlay flags here if that ever bites.
+  // they stay volume keys. The modals need no flag of their own: an RN
+  // Modal is a window of its own and holds the focus, so the activity never
+  // sees a key while one is up.
   useEffect(() => {
     VolumeShutter.setEnabled(mode === 'camera');
   }, [mode]);