create a txt file and save it in, e.g. /home/"user" whatever it may be called. 
In a plasma-wayland session, try to open Dolphin to visualize the file. 
click on it and select "open with kate" or "open with notepad". Nothing
happens. 
Try open with libreoffice (opens but the first instance will silently crash and
immediately open again, working and displaying correctly the file. 

I then tried to open from the start menu a virgin kate or a virgin notepad.
These do open. 
>From inside the program it is normally possible to open the aforementioned file
without problems.