Actually I did delete ~/.local/share/kscreen as well but I had done that a day before I deleted the other file. Maybe it needed both. Wont be able to know unless it’s tested and I don’t know how to get back to a broken state.

Good catch though, i didn’t even think that might be relevant till you said something!

I don’t think deleting kwinoutputconfig.json will work being logged in, according to this KDE discussion where I got my info for the fix. I guess you could probably login to the terminal as root if you have root setup.

Hope this thread helps the next person that has the issue!