Often (but not always..) when I wake my blanked screen (Suspend is disabled), I have been reverted back to ~600x400 resolution with what looks like 16-bit color (Can’t remember exactly). After unlock, when I go to System Settings → Display & Monitor it says that I cannot change resolutions.
Restarting corrects the issue.
I’ve tried to work around it by:
Switching from KDE+Wayland to KDE+X11
kquitapp5 plasmashell
kstart5 plasmashell
systemctl restart sddm
I’ve just recently tried to disable “KScreen 2” from “Background Services” however I’m not sure if this has helped yet. While disabling that, I noticed the note at the top “If you’re disabling something here to work around an issue, please submit a bug report about it as well.” and so instead of reporting a bug I came here. I couldn’t find anything by searching that seems relevant.
I’m new to KDE so apologies if I’ve categorized this incorrectly.
P.S: I’m posting instead of waiting to see if disabling “KScreen 2” works around the issue because there was approximately ~14 hours since the last time this happened (Sorry; hoping to skip a lengthy troubleshooting scenario by asking for help).
Update 2: While KScreen 2 is disabled, manually turning my monitor off and then on again seems to kill/disrupt plasmashell.
However, I still have all my resolution & colour once I manually kill/start plasmashell. Very interesting
.. Going to try to turn KScreen 2 back on and see if I still have issues with the plasmashell while turning the monitor on/off again lol.
Update 1: Perhaps I’ve made things worse by disabling “KScreen 2”. For the most recent test I:
Disabled dimming and turning off the screen
(Suspend is always disabled for my testing/uses)
Manually turned my monitor off after lock screen was displayed for ~10 minutes
When I turned on the monitor the locked screen was there (Looking beautiful, by the way..) however after I unlocked, plasmashell either crashed or was not running (It was just a black screen with no desktop icons or panels).
KRunner was still there (Alt+F2) and so I tried to manually start plasmashell from Konsole with kstart5 plasmashell
The command ran but didn’t output or change anything. So then I did:
kquitapp5 plasmashell
kstart5 plasmashell
That got my shell back. Peculiar!
Not sure if it’s related (I’m pretty lost, sorry).
Update 3: Can confirm that disabling/stopping KScreen 2 is what is causing me to lose plasmashell when I turn the monitor off/on.
I suppose that makes sense, too.. lol. Honestly manually restarting plasmashell is MUCH less disruptive to me than losing resolution, colour and refresh rates (Unless somebody knows how to quickly restart something that wont log me out or kill my running processes?)
I’ll keep KScreen 2 off and run the system for a couple days and/or until the main problem occurs again (Or doesn’t) and report back my findings.
Update 4: The disabling of “KScreen 2” workaround is not viable. Although it is less of a blocking issue than the original issue, it is significant still.
After many combinations of screen lock/unlock events & monitor off/on events, when “KScreen 2” is not running I retain my resolutions and most apps retain full colour. However, all of my Chromium-based browsers revert back to ~16-bit color.
Here is a full-window screenshot showing Edge displaying ~16-bit colours (Look at the CoPilot icon in the top-right corner to really see the affect).. Juxtaposed above my full-colour plasma panel icons below it:
Update 5 - I installed the xfce desktop environment in Fedora 43 and the video bug is gone..
I can manually turn my monitor on/off, manually lock the screen (xflock) and/or let the power mangement turn my monitor off & lock. No change in my resolution or anything.
)
