Wayland primary selection interoperability with GTK clients

[Bernie Innocenti]

Greetings distro packagers!

One of the few remaining blockers for KDE on Wayland involves middle 
click pasting between Wayland clients and GTK clients running on 
XWayland, like for example Chromium and Firefox.

KDE implemented the standard protocol (zwp_primary_selection) a while 
ago: https://bugs.kde.org/show_bug.cgi?id=422426

Whereas GTK support landed only last month, missing the 3.24.23 dot 
release: https://gitlab.gnome.org/GNOME/gtk/-/issues/2591

Upstream GTK developer Emmanuele Bassi said that there are no more gtk3 
dot releases planned (at least not before GTK 4.0 is released). 
Emmanuale recommends cherry-picking this patch from the gtk-3-24 stable 
branch to distro packages:

https://gitlab.gnome.org/GNOME/gtk/-/commit/9a693c7228a88b76a007aed41b101d89d084cf9b

To verify that the patch works:
1. Log into a Plasma Wayland session
2. Open a gtk3 client using X11, such as Chromium or Firefox
3. Select some text
4. Open any Wayland client, for example Konsole
5. Try pasting the text with the middle mouse button

-- 
_ // Bernie Innocenti
\X/  https://codewiz.org/