App hangs when entering Voice Messages' locked recording mode after ~1:30 minutes

### Steps to reproduce

1. Open a room you can post in.
2. Start a voice recording by holding your finger on the screen.
3. After a minute and a bit, move your finger upwards to enter locked recording mode.

### Outcome

#### What did you expect?
No UI lag. No app crashes.

#### What happened instead?
1. App hangs when entering the locked mode.
2. Android repeatedly offers to kill the app or report an error to Google (and/or the developer).
3. After 2-3 minutes. The app flashes all white and restarts its webview or something. Then it is back to normal, but your voice recording is lost.

### Your phone model

One Plus 5

### Operating system version

Android 10

### Application version and app store

1.4.16 on Google Play Store

### Homeserver

EMS; latest Synapse

### Will you send logs?

Yes

### Are you willing to provide a PR?

No