1743474 - Video in fullscreen windowed mode scales the video image incorrectly

Status: VERIFIED FIXED

(Core :: Graphics: WebRender, defect)

Description

[Brad Werth [:bradwerth]]

Steps to Reproduce:

1. View a YouTube video such as https://www.youtube.com/watch?v=aqz-KE-bpKQ.
2. Start the movie playing, then pause it.
3. Click the fullscreen window widget in the window toolbar (the round green button in the upper left).

Expected Results:
The window expands to fill the screen, and the video is sized correctly in its frame.

Actual Results:
The window expands, but the video is scaled as if it is also filling the screen.

Comment 1

[Markus Stange [:mstange]]

Comment 2

[Brad Werth [:bradwerth]]

The problem here is that the NativeLayerCA::SetRootWindowIsFullscreen call triggers the conditions that allow an OnlyVideo update, which simultaneously isn't picking up the fact that the video layer size has changed. The fix will be ensuring that the change to the video layer size is properly noted in a mutation bit.

Comment 3

[Brad Werth [:bradwerth]]

Attachment: Bug 1743474: Make NativeLayerCA set size and scale when recreating layers.

Most of the time, layer mutations that recreate layers also set their size.
A fullscreen transition can create a layer mutation without setting the size
mutation bit. This change ensures that newly-created layers are always sized.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/de26032fc7b9
Make NativeLayerCA set size and scale when recreating layers. r=mstange

Comment 5

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/de26032fc7b9

Comment 6

[Ryan VanderMeulen [:RyanVM]]

Should we consider taking this on Beta?

Comment 7

[Brad Werth [:bradwerth]]

Comment on attachment 9253321 [details]
Bug 1743474: Make NativeLayerCA set size and scale when recreating layers.

Beta/Release Uplift Approval Request

• User impact if declined: macOS users viewing video and then transitioning to fullscreen will have improperly scaled video.
• Is this code covered by automated tests?: No
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): This is a minimal correctness change that has very little possibility of causing new issues to appear.
• String changes made/needed:

Comment 8

[Dianna Smith [:diannaS]]

https://hg.mozilla.org/releases/mozilla-beta/rev/e37539bfcbfc

Comment 9

[Dianna Smith [:diannaS]]

Comment on attachment 9253321 [details]
Bug 1743474: Make NativeLayerCA set size and scale when recreating layers.

Approved for 96.0b5

Comment 10

[Monica Chiorean]

I was able to reproduce the issue on Mac 10.13 using NB 96.0a1(29-11-2021).
Verified as fixed on Mac 10.13 using NB 97.0a1(20211215091158) and Beta 96.0b5(20211214203716).