Comment 15 for bug 1879968

I wanted to let you know that I am experiencing very similar behaviour on Kubuntu 20.04 after updating from 18.04 to 20.04, and I have my doubts that it's related to Mutter. For now I can confirm that I have an issue on KDE Plasma - to be able to paste (middle mouse click, Ctrl+C/V or Copy/Paste context menu options), I have to copy the same text twice, in one of the ways described below:
1. select text (ie. double click it), then click anywhere to lose focus from it, then select exactly the same text again - then I am able to paste with middle mouse button; or:
2. when text is already selected, I need to hit Ctrl+C twice, then I can paste it with Ctrl+V.
Above is suspiciously close to what Davide mentioned above in comment https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1879968/comments/3 and that's why I decided my problem is probably related.

My suspicion - this may be related to some application I use. On KDE this issue manifests almost right away after logging in now, but there's a short period after logging in, when it doesn't happen yet. Maybe I've got something in autostart that triggers it.

On other environments (Openbox, LXQT and Gnome Shell) I did not experience this problem, however I did test only for a minute. My plan for next few days is to switch to LXQT and wait for the problem to happen again, and let you know.