This reverts commit e60f26e0.
Cancelling the primary selection breaks text selection in applications such as gedit. In those apps, you can't select text neither with your mouse nor keyboard.
- Qt applications must handle the withdrawal of the primary selection manager global. This is a must-have because Qt apps are predominant in Plasma. Qt 6 patch: https://codereview.qt-project.org/c/qt/qtwayland/+/435336
- GTK applications need fixing too. I created a gtk 3.24 patch https://gitlab.gnome.org/GNOME/gtk/-/merge_requests/5067, gtk 4 is a much harder one because clipboard abstractions changed a lot there, still doable. It would be great to get GTK patch merged, but I don't think it should be a blocker for this one
In either case, I think that it's worth reverting e60f26e0. An app crashing after disabling primary selection is not great, but it's one time only and it's less damaging than getting broken text selection on a reboot or app relaunch.