[Intermittent] Firefox crashes when adding the app to the background

[abodea]

Steps to reproduce

1. Launch FF in single window mode
2. Open password screen, enter password/biometrics
3. Let app sit

Result: the app will continue eating memory until a system crash.

Alternative steps to reproduce

1. Launch FF and enter split view.
2. On window 1 access the password section (add the password/any biometrics to see the password section).
3. Add FF to the background.
4. Wait on the springboard -> FF crashes.

1. Expected behavior

Firefox should not crash after adding it to the background.
1. Actual behavior
Firefox crashes when adding the app to the background while being in split view mode.
1. Device & build information

• Device: iPad Air 3rd gen (17.5.1), iPad Air (16.4), iPad Pro 4th gen (17.2).
• Build version: v9000 (42878)
• First seen version: v9000 (42878)

*#
*## Notes
Please note that I tried on v128 (42870) but cannot reproduce this issue.
Attachments:

Crashlogs.zip

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┆Issue is synchronized with this Jira Task

[data-sync-user]

➤ Matt Reagan commented:

This can be reproduced in single-window mode as well, and doesn’t look related to multi-window. (cc Andrei Bodea ) I’m going to update the title and description for this.

[data-sync-user]

➤ Matt Reagan commented:

Note: some of the attached IPS are slightly different, but I’ve been able to replicate this directly and the root problem is that whenever the password screen is open the app begins eating memory continually non-stop until an eventual system crash.

[data-sync-user]

➤ Matt Reagan commented:

Update: ran a bisect and it appears this was introduced by the recent theme manager refactor (#20667 ( https://github.com/mozilla-mobile/firefox-ios/pull/20667|smart-link ) )

[data-sync-user]

➤ Andrei Bodea commented:

Verified as fixed on v9000 (43298) with iPad Pro (16.4.1).

[data-sync-user]

➤ Diana Andreea Barladeanu commented:

Verified as fixed on v129 (43576) with iPad Air 3rd gen (17.5).