Steps to reproduce: 1. Start Dolphin and copy some text in it - for example - copy file name text upon renaming of a file. 2. Start Firefox and try to paste previously copied text in some field. Selected file name is copying to system Clipboard and pasting normally into other app - for example into Kate. Right click 'Paste' menu item is disabled if Firefox. Not sure if this is Wayland Plasma or Firefox bug.
There is no support to copy and paste between wayland and xwayland windows yet.
Probably. But as this report has no backtrace we can't know for sure. I'm going to have to close it anyway.