1874490 - Transition animation plays on wrong page when changing tab while in fullscreen

Status: UNCONFIRMED

(Core :: DOM: Core & HTML, defect)

Description

[Jacob Bundgaard]

Attachment: Screen recording showing the current behavior

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:121.0) Gecko/20100101 Firefox/121.0

Steps to reproduce:

1. Open a page in fullscreen, for example a video on YouTube.
2. Switch tabs without exiting fullscreen first, for example with Ctrl + Tab or Ctrl + Number key.

Actual results:

Firefox briefly displays the new tab, then shows the transition animation for leaving fullscreen, then shows the new tab. See attached screen recording.

Expected results:

Firefox should either:

1. Skip the fullscreen transition animation when the user switches tab, or
2. Play the fullscreen transition animation on the previous tab, then switch to the new tab after it's done.

I would prefer option 1. In any case, Firefox should not show the "flash of new page" before playing the animation.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::CSS Transitions and Animations' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Brian Birtles (:birtles)]

Note sure what this is but it's not CSS transitions.

Comment 3

[Jacob Bundgaard]

The transition duration is controlled by configuration settings under full-screen-api.transition-duration. I'm not sure if that says anything about which component it's under.

Comment 4

[Neha Kochar [:neha]]

I could not repro this. Moving it to Firefox --> Tabbed Browser. Hopefully that is the right match.
I also see these bugs that sound similar/dups which someone from the right module should review & confirm too:
https://bugzilla.mozilla.org/show_bug.cgi?id=1845733
https://bugzilla.mozilla.org/show_bug.cgi?id=1483673

Comment 5

[Jacob Bundgaard]

Just to be sure it isn't a problem with my setup, I reproduced this in two new virtual machines, one with Windows 10 and one with Windows 11, both with a clean Firefox install. The glimpse of the new tab isn't always shown for that long before the transition, so you may have to try a few times to catch it, depending on the PC.

I didn't find the two bugs you linked when searching earlier, but the first one sounds very similar and the second one may be describing a cause.

Comment 6

[Negritas Sergiu, Desktop QA]

Hello! I think I have managed to reproduce the issue in some on Windows 11 with firefox 121.0.1, but just to make sure could you please send a screen capture with the issue just to make sure it's the same in order to change the status of this issue.

Thank you and have a nice day!

Comment 7

[Jacob Bundgaard]

Have a look at the attachment for the bug. :-)

Comment 8

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:dao, could you have a look please?

For more information, please visit BugBot documentation.

Comment 9

[Dão Gottwald [:dao]]

(In reply to Jacob Bundgaard from comment #3)

The transition duration is controlled by configuration settings under full-screen-api.transition-duration. I'm not sure if that says anything about which component it's under.

Yeah, the code using those prefs lives in nsGlobalWindowOuter.cpp.

Comment 10

[Henri Sivonen (:hsivonen)]

Edgar, are you the right person to take a look at this?

Comment 11

[Edgar Chen [:edgar]]

I think this is a long existing behavior, I am not sure if we would like to suppress showing transition for this case. And since the glimpse of the new tab isn't shown too long, I feel this is a minor issue, but perhaps something we could try to improve.