PSA: Update to Plasma 6.3 can make Wayland session unusable if you have configured monitor ICC profiles

bugs.kde.org

499789 – Setting an ICC profile in Display Configuration causes screen to blank when KWin is compiled with GCC and LTO

Update: Bug fixed in Plasma 6.3.1

Just posting this since I spent over an hour trying to figure out why I couldn't open my desktop today.. After booting and logging in I got a black screen. Switched to a terminal but did not see any obvious errors in the logs.

Not fixed for Fedora 41 KDE yet, so I installed plasma-workspace-x11 to use in the meanwhile. Anyone who hasn't updated to 6.3 yet could probably change their display settings to not use ICC profiles to avoid it.___

7 comments

This is the sort of shit that btrfs snapshots (snapper) was made for. Boot after update, something is borked, no obvious problem or solution, fuck this take me back

This is kinda unrelated to the post but do icc profiles now generally work on wayland? I thought last time i read about it it didn't work yet but maybe i'm mistaken.
- KDE has had ICC support implemented for a while now in Wayland. The necessary protocol for ICC support/color management in Wayland recently got merged, so the next release of many popular compositors (plasma 6.3 for KDE) will be protocol-compliant.
  
  That's great, thanks for the info!

Damn, so that was the issue. I spent 2h trying around with different packages I suspected to cause an error during start. Then I desperately moved my .config dir out of the way to rule out an incompatible config and lo and behold... it worked. I then moved it back and tried to delete configs more finegranular. After a few iterations without success I just removed almost all kde and plasma related configs and reconfigured everything from scratch. I should have scrolled through my feed earlier 😁
- It was surprisingly difficult to find, the majority of comments about 6.3 were people saying it was working great, but I guess most people don't use ICC profiles for their monitors.

I had something similar happen in Plasma 6.1 and 6.2. After I turned off the dccutils support in powerdevil, I have not had the issue since. My desktop is not a laptop, so it's always powered, same with screen, so I don't need fancy power profiles.

7 comments