Crash at tapping group call button

[kaktusztea]

• [x] I have searched open and closed issues for duplicates
• [x] I am submitting a bug report for existing functionality that does not work as intended
• [x] This isn't a feature request or a discussion topic

---

Bug description

Crash after tapping on group call (camera) icon.

Steps to reproduce

Not reproducable.

I did this:

• opened a group chat
• browsed between stickers a lot. Not sent any of them
• switched back to keyboard
• tap on group call (camera) button above

Device info

Device: iPhone SE 2020

iOS version: 15.7

Signal version: 6.6.0

Link to debug log

Restarted Signal, tried to reproduce the issue (could not), then collected this debug log. https://debuglogs.org/ios/6.6.0/2350f262071547d7af410f533e5bc45762c04b365ff746872bb98d55af66a37e.zip

[kaktusztea]

Crash log sent in email.

[EvanHahn-Signal]

I reviewed your logs. It looks like a catastrophic failure creating a system thread, which should be rare.

If it happens again, let us know.

[kaktusztea]

OK, will reopen if it happens again.