Running element call in Google Chrome on IOS is not a good experience. Incoming Phone calls drop me from the call. Joining back in, I'm unmuted

### Steps to reproduce

1. Where are you starting? What can you see?
I Join a call on my Iphone in Google Chrome. Statup / joining takes too long, getting permissions for Microphone and Camera takes long.

When I'm in the call and get a phone call, the Browser shifts to the background and the call is dropped. There is currently no way to put the Element Call into the background. The call will be dropped.

I did decline the phone call, had to rejoin the Element Call. It did not remember that I wanted to join muted.

This happend for the 2nd time now.

### Outcome

#### What did you expect?

I should be able to lock my screen / put Element Call in the background. I would expect my audio to continue. If I drop from the call, joining back in should be seemless. It should remember that I was muted on that call.

#### What happened instead?
Can't put the Element Call in the background.
Rejoin unmuted.

### Operating system

IOS

### Browser information

Google Chrome

### URL for webapp

Element All Hands call

### Will you send logs?

Yes

No files, tests, or entry points are named. Start by reproducing the call interruption and rejoin flow in Google Chrome on iOS, then trace what happens when the app is backgrounded and when microphone state is restored. Done means the call handles backgrounding or interruption as expected and a rejoin preserves the muted state.

Written by the indexing model from the issue text.