pdf page jumps to top upon switching to other app or calling out dock

[Prurite]

Steps to reproduce

1. Open a multiple page pdf and scroll down a bit
2. Swipe from the bottom to call out the dock, or change focus to another app when using Stage Manager
3. Switch focus back

Expected behavior

Firefox remembers the position of the opened pdf document

Actual behavior

Page jumps to top

Device & build information

• Device: iPad Pro M2 11-inch, iPadOS 17.2
• Build version: 124.0 (39709)
• First seen version: ?

Notes

Attachments:

https://github.com/mozilla-mobile/firefox-ios/assets/44775584/9735bd44-e9b5-4aab-b44a-920f66eab840

https://github.com/mozilla-mobile/firefox-ios/assets/44775584/0d1d2e16-a507-4f20-9834-b2f5f6e26735

Another annoying pdf related issue: Opening a link in a pdf tab causes all tabs of pdf to jump to that page #17519

┆Issue is synchronized with this Jira Task

[data-sync-user]

➤ Alexandru Farcasanu commented:

I looked over this for a while, I can reproduce this issue easily but unfortunately I am not able to find a fix for it. (maybe someone with a better knowledge on this side, can take a look)

What I found? This behaviour is impacted by the Toolbar animation, more exactly when showToolbars(animated: Bool) method is called and the headerTopConstraint is updated/changed.

This is happening only on iPad (as I tested), only when the Toolbar is hidden and we open the app, from the background. (and only for PDFs)

!Screen Recording 2024-04-15 at 12.54.11.mov|width=2406,height=2012,alt="Screen Recording 2024-04-15 at 12.54.11.mov"!

[data-sync-user]

➤ Nishant Bhasin commented:

FYI: https://mozilla-hub.atlassian.net/browse/FXIOS-8928 ( https://mozilla-hub.atlassian.net/browse/FXIOS-8928|smart-link ) from Cyndi Chin

[data-sync-user]

➤ Alexandru Farcasanu commented:

Winnie Teichmann some thoughts here? Thank you.

[data-sync-user]

➤ Alexandru Farcasanu commented:

News here.

After a/an sync/investigation with/from Winnie Teichmann, a quick call with Sorin Paraipan and few more investigations from me, we found this: this issue is more reproducible starting with the current latest iOS version (17.4).

We can reproduce this, easily, on iOS versions like 17.2 (only on iPads) but no more issues on 17.4 version, the recent one.

I am moving it to the QA team, in order to be verified this behaviour. Andrei Bodea

!Screen Recording 2024-04-17 at 15.09.31.mov|width=2422,height=2012,alt="Screen Recording 2024-04-17 at 15.09.31.mov"!

cc: Norberto Andres Furlan

[data-sync-user]

➤ Diana Andreea Barladeanu commented:

Hello, the issue is still reproducible.

Verified on v126 (41303), with iPhone 15 (17.4).

!RPReplay_Final1714388132.mp4|width=590,height=1280,alt="RPReplay_Final1714388132.mp4"!

[data-sync-user]

➤ Alexandru Farcasanu commented:

Thank you Diana Andreea Barladeanu

This problem appeared again after the implementation for this ticket https://mozilla-hub.atlassian.net/browse/FXIOS-8941 ( https://mozilla-hub.atlassian.net/browse/FXIOS-8941|smart-link ).

Should find another fix. 🤞

[data-sync-user]

➤ Alina Moldovan commented:

Rechecked this issue using FF v126 (41600)

Not able to reproduce it using the iPhone device but it reproduces using iPads

!Skype_Video2.mp4|width=1342,height=1920,alt="Skype_Video2.mp4"!

[data-sync-user]

➤ Alexandru Farcasanu commented:

Alina Moldovan what is the OS version on the iPads that you used? Thank you.

[data-sync-user]

➤ Alina Moldovan commented:

Here are the device details: iPad Pro 4th gen (17.2)

[data-sync-user]

➤ Diana Andreea Barladeanu commented:

Verified as fixed on v126 (41600), with iPad Air 3rd gen (17.5) and with iPhone 15 (17.4.1).