1753774 - Firefox does not re-render properly in Wayland mode on KDE

Status: RESOLVED DUPLICATE of bug 1616894

(Core :: Widget: Gtk, defect)

Description

[Botond Ballo [:botond] [away until Jun 24]]

Attachment: about:support

STR

1. Log into a "Plasma (Wayland)" session. My OS is PureOS Byzantium, which I believe is based on Debian testing, but I'm not sure what package versions are relevant here.
2. Run latest Firefox Nightly with MOZ_ENABLE_WAYLAND=1 in the environment.
3. Try to interact with the browser, such as typing into the URL bar or scrolling.

Actual results

The browser does not re-render in response to key presses or scrolling. However, if you switch away from the Firefox window and switch back, the rendering has now updated (e.g. the typed characters now appear in the URL bar).

Expected results

Normal rendering.

about:support is attached.

Comment 1

[Botond Ballo [:botond] [away until Jun 24]]

In a "GNOME (Wayland)" session on the same machine, the behaviour is fine.

Comment 2

[Darkspirit]

Nightly already has MOZ_ENABLE_WAYLAND=1 by default unless the Gtk version is too old (>= 3.24.30 bug 1749174).

KDE Wayland, Debian Testing, Intel
I can't seem to reproduce this bug.

$ dpkg -l | grep "libgtk-3-common\|kwin-wayland"
ii  kwin-wayland                                  4:5.23.5-1                         amd64        KDE window manager, wayland version, PREVIEW release
ii  kwin-wayland-backend-drm                      4:5.23.5-1                         amd64        KDE window manager drm plugin
ii  libgtk-3-common                               3.24.31-1                          all          common files for the GTK graphical user interface library

Which versions do you have?
$ dpkg -l | grep "libgtk-3-common\|kwin-wayland"

Comment 3

[Vlad Zahorodnii [:zzag]]

After some quick googling, it looks like PureOS Byzantium ships Plasma 5.20, which is old and I believe it doesn't handle well how firefox uses frame callbacks. Can you try setting widget.wayland.vsync.enabled to false in about:config?

Comment 4

[Botond Ballo [:botond] [away until Jun 24]]

(In reply to Darkspirit from comment #2)

Which versions do you have?
$ dpkg -l | grep "libgtk-3-common\|kwin-wayland"

A bit older than Debian testing, it seems

$ dpkg -l | grep "libgtk-3-common\|kwin-wayland"
ii  kwin-wayland                                  4:5.20.5-1                       amd64        KDE window manager, wayland version, PREVIEW release
ii  kwin-wayland-backend-drm                      4:5.20.5-1                       amd64        KDE window manager drm plugin
ii  libgtk-3-common                               3.24.27-1pureos4                 all          common files for the GTK graphical user interface library

Comment 5

[Botond Ballo [:botond] [away until Jun 24]]

(In reply to Vlad Zahorodnii [:zzag] from comment #3)

Can you try setting widget.wayland.vsync.enabled to false in about:config?

That does appear to fix the problem -- thanks!