I was trying to install nvidia drivers  beacause the screen latency was s l o o w. Eventually I goto the point where I gon black screens with a brief message about unsupported resolution. Just for on user though. I created a new user just to to test this and coul log in to KDE normally.

Since this was a user specific issue, and I created a new user jut to test tthis, I figured that something was corrupted in ~/.config right? So I restored it from yesterdays, working, backup and no change.

It turns out that there another directory,  in ~/.local/share/kscreen, where KDE saves all the screens ever atteched to the computer! So everytime you fuck about with screen settings ro drivers another file is created. Mine had several files in there, I have two monitors only. I'm asssuming that KED/Pulse was reading and writing to these fictitous/bogus/virtual screens mutilplicatly (several times?) and thus slowing both input and output. Maybe, as I can't find any documentation for this, but evetually a forum led me this way.

I logged out. Did init 3 as root in a ctrl+F4 terminal and then deleted the direcotory.  Did init 5 and logged in again. Got KDE normal desktop back and with no lag. Result.

How fucking annoying though that KDE stores screen info in ~/.share and not in ~/.config? What the fuck! Also since deleting it fixed th eissue it appesars that there' not reason to store it it all anyway.

So why the fuck does KDE do this? If it needs to, why is it not in ~.config? Fuck you. What purpose is served by this?

This took almost a day trying install Nvidia drivers ( to cure the lag issue), reverting, installing , repeat...

TODO: report this as a bug.

Other on-line references:

https://ask.fedoraproject.org/t/x11-screen-resolution-bug-in-kde-settings/19347/7

https://forum.level1techs.com/t/multi-monitor-setup-was-just-wrecked-any-way-to-recover-the-old-config/149001/5

Last changed: 29. January, 2022 at 00:30