Walkie-talkie UI doesn't scale well to short windows

[dbkr]

Steps to reproduce

Start or enter walkie talkie mode call

Outcome

What did you expect?

Back & hangup buttons

What happened instead?

No buttons

Looks like they're there but have been pushed off the screen

Operating system

No response

Browser information

No response

URL for webapp

No response

Will you send logs?

No

[dbkr]

Oh, only happens if the window isn't very tall

[dbkr]

Actually I don't think this is a regression (although it's not ideal that the walkie-talkie mode interface needs most of the height of a full HD monitor to display properly).