1794577 - [wayland] Picture-in-picture window height gets 52px smaller each time it is opened

Status: VERIFIED FIXED

(Core :: Widget: Gtk, defect, P3)

Description

[Kestrel]

Attachment: Video showing pip window shrinking each time it is opened.

STR:

1. Start with MOZ_ENABLE_WAYLAND=1 on Ubuntu 22.04.
2. Open a video in Picture-in-Picture.
3. Close it and reopen it multiple times.

The video height shrinks by 52px each time it is opened with the width following the aspect ratio of the video. It stops shrinking when the window height reaches 80px.

Does not happen with X11/XWayland.

Regression window:
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=2977d4891ceeed019dc906dff3feb6c9f530213c&tochange=5278acfcd8344d6cd0a3f5bfb6cab6d68a9e93bc

Likely regressed by Bug 1578985.

Comment 1

[Martin Stránský [:stransky] (ni? me)]

I guess it's wrong size calculation related to CSD border size.

Comment 3

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

Set release status flags based on info from the regressing bug 1578985

Comment 5

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

The following field has been copied from a duplicate bug:

Field	Value	Source
Regressed by	bug 1749174	bug 1818338

For more information, please visit auto_nag documentation.

Comment 6

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1794577 - Minor clean-up to CSD code. r=stransky

No behavior change.

Comment 7

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1794577 - Clear decorations from PiP window earlier during creation. r=stransky

What is going on here is a bad interaction between the
aspect-ratio-locking that PiP uses and CSD.

The Wayland window starts off with CSD decorations. That adds some
margin to our windows. When we un-decorate the window then eventually
GDK removes those margins, which means that we end up with a different
size, due to the aspect ratio.

PiP is special enough that is probably ok to just do this.

Depends on D171074

Comment 8

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1794577 - Set dummy titlebar for always-undecorated windows. r=stransky

This prevents the system titlebar from showing up in Plasma+Wayland.

Depends on D171075

Comment 9

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1794577 - Enable aspect-ratio locking on KDE too. r=stransky

Seems to work nicely.

Depends on D171076

Comment 10

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/2bbe62fb0734
Minor clean-up to CSD code. r=stransky
https://hg.mozilla.org/integration/autoland/rev/bcea4f6871b4
Clear decorations from PiP window earlier during creation. r=stransky
https://hg.mozilla.org/integration/autoland/rev/5eef5f5abf22
Set dummy titlebar for always-undecorated windows. r=stransky
https://hg.mozilla.org/integration/autoland/rev/d330f257bf95
Enable aspect-ratio locking on KDE too. r=stransky

Comment 11

[Marian-Vasile Laza]

https://hg.mozilla.org/mozilla-central/rev/2bbe62fb0734
https://hg.mozilla.org/mozilla-central/rev/bcea4f6871b4
https://hg.mozilla.org/mozilla-central/rev/5eef5f5abf22
https://hg.mozilla.org/mozilla-central/rev/d330f257bf95

Comment 12

[Giorgia Nichita, Release Desktop QA]

Reproduced this issue on an affected Nightly build from 2022-10-11, on Ubuntu 22.04 on Wayland.
Verified as fixed on Firefox 112.0 (20230403163424) and Firefox 113.0a1 (20230403092724) on the above platform. The Picture-in-picture window no longer shrinks.