Enabling a Second Monitor connected via DP-DaisyChain immediately disables it again

Hello everyone,

I’ve updated to plasma 6 with the hope that my multi monitor setup works now but unfortunately it doesn’t. That’s why I seek the help of you. But before reporting a bug I’d like to see if it’s a configuration issue on my side.

I’ve tested with screen-doctor -o and found the second monitor (which is nice) but it seems to be disabled.

So I tried to enable it with kscreen-doctor output.DP-12.enable (DP-12 being the disabled monitor) and the output seemed good but nothing changed.

Enabling output 3
kscreen.doctor: setop exec returned KScreen::Config( 
KScreen::Output(1, "eDP-2", connected enabled priority 2, pos: QPoint(3072,280), res: QSize(2560, 1600), modeId: "0", scale: 1.75, clone: no, rotation: KScreen::Output::None, followPreferredMode: false) 
KScreen::Output(2, "DP-10", connected enabled priority 1, pos: QPoint(0,0), res: QSize(3840, 2160), modeId: "0", scale: 1.25, clone: no, rotation: KScreen::Output::None, followPreferredMode: false) 
KScreen::Output(3, "DP-12", connected enabled priority 3, pos: QPoint(6400,0), res: QSize(3840, 2160), modeId: "0", scale: 1.75, clone: no, rotation: KScreen::Output::None, followPreferredMode: false) )

I’ve also checked it in the Display Configuration settings and tried to enable it there but whenever I press apply it it also immediately jumps back to the old state.


Quick Update:
Just tested it and disabled my Built-In laptop monitor and enabled the screen afterwards. Now the config enabled the screen but it didn’t turn on but just stayed black.

Enabling the laptop monitor then removed the second external monitor again…
Is there anything I can provide in terms of logs that might help to debug the issue?

Thanks a lot!

In case anyone comes across this issue. I’ve filed a bug report in the kde issue tracker with id: 484910
(cannot post links)