1721036 - [Wayland] Popups are not shown with multi-buffer backend

Status: VERIFIED FIXED

(Core :: Widget: Gtk, defect, P1)

Description

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

When multi-buffer backend is used, some popups are not painted.

Reproduction steps:

1. Go to about:preferences#home
2. Click on any combo box there.
3. The combo box button looks active (pressed) but popup window under it is not shown.
4. Move mouse under the combo box (where a popup should be painted) and you'll see popup content now.

For debugging you also can remove gtk_widget_set_app_paintable() calls from nsWindow::Create(), all popups won't be transparent and you'll see if popup content is painted or not.

Robert, can you please look at it?
Thanks.

Comment 1

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

Also when mouse cursor is moved over menu toolbar some menu are not painted (I expect the same reason).

Comment 2

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

Attachment: Screencast-popups.webm

Screencast of the issue.

Comment 3

[Robert Mader [:rmader]]

Indeed, will look into it! I also affects the compositor backend (which uses very similar logic), so I must have made a logic mistake in both of them.

Comment 4

[Robert Mader [:rmader]]

Attachment: Bug 1721036 - Do not wait for surface ready_to_draw on multi buffer backend, r=stransky

moz_container_wayland_surface_lock currently only returns a valid
surface if ready_to_draw is set. This results in initial draws
not getting submitted, which the single buffer backend handles by
adding a timer.

For the multi-buffered backend there's no obvious reason to wait -
the buffer can already be attached and will become visible once the
surface gets mapped.

Comment 5

[Robert Mader [:rmader]]

Blocking bug 1617498 as it's similarly affected and we might be able to come up with a common solution here.

Comment 7

[Robert Mader [:rmader]]

Attachment: Bug 1721036 - Delay buffer commits until the surface is ready,r=stransky

When the MozContainer surface is not yet ready in Commit(),
we need to queue the commit.
Similar to nsWindow and WaylandVsyncSource we can do so by
registering via a callback via add_initial_draw_callback().

This required some logic changes which let to clean ups and
simplifications in the whole file (I'm sorry it got so big).

Comment 8

[Robert Mader [:rmader]]

https://treeherder.mozilla.org/jobs?repo=try&revision=a7d9640149e510cadf0fcef51c9a94bb1bd83561

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/50735532fcdf
Delay buffer commits until the surface is ready,r=stransky

Comment 10

[Atila Butkovits]

https://hg.mozilla.org/mozilla-central/rev/50735532fcdf

Comment 11

[Catalin Sasca, Desktop QA [:csasca]]

Reproduced the issue on Firefox 92.0a1 (2021-07-17) under Ubuntu 20.04 Wayland by following the STR from Comment 0.

The issue is no longer reproducible on Firefox 92.0 on the same system.