Bug#1002651: Please cherry-pick the commits after the 3.38.6 release from upstream to bullseye-updates

[Simon McVittie]

On Sun, 26 Dec 2021 at 16:28:36 +0000, Amr Ibrahim wrote:
> Please cherry-pick the commits after the 3.38.6 release from upstream
> gnome-3-38 branch to bullseye-updates. Or maybe upstream could release
> 3.38.7.
> 
> The commits are Wayland fixes mainly for the sake of newer versions of
> Firefox, which can be installed as a flatpak in Debian 11.

Which commits do you have in mind and what bugs do they fix? The more
we backport, the higher the risk of regressions is, particularly if those
commits aren't in a formal release yet.

0db4ac73 "wayland/subsurface: Check for parent actor before unparenting",
60afd63e "wayland/subsurface: Handle node unlinking on parent destroyed",
58343f43 "window-actor/wayland: Remove subsurface actors on dispose"
seem to be fixing crashes with native Wayland apps that use subsurfaces,
and in particular Firefox. Is that correct?

bb85f21d "xwayland: Fix condition for queuing a window to
META_QUEUE_CALC_SHOWING" seems to be preventing unnecessary event messages
from being sent to X11 apps in Wayland, so it's fixing a performance problem.
Is that correct?

5a6b3c4b "wayland/data-offer: Accept final preferrence of drop destination"
seems to be fixing a protocol error that would result in Firefox being
terminated during Alt + drag-and-drop. Is that correct?

15ac84da "surface-actor: Fix unobscurred_fraction calculation" seems to be
fixing an incorrect refresh rate when fullscreen apps in multi-monitor
setups use Vsync. Is that correct?

For
a9e60bad "wayland/surface: Switch order for calculating surface damage",
aeda2cbc "wayland/surface: Use correct default viewport for surface damage",
0b26ad63 "wayland/surface: Do not uncoditionally process surface damage"
I don't understand what bug they are fixing, so I am going to find it hard
to "sell" this change to the release team: we can't weigh up benefit vs.
regression risk if we don't understand the benefit. If you need these changes,
please could you explain the impact to bullseye users of not having them?
I've also asked for clarification on the upstream MR
<https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2168>.

Thanks,
    smcv