SUMMARY My system has 3 displays attached. 2 identical screens and a third TV, spread out over DisplayPort and HDMI. UP til somewhere in 5.27 I've been able to configure these all via the KCM, re-order and place them using the "Drag screens to re-arrange them" view. However since recently the TV doesn't appear on that screen anymore. It's still under the "Device" dropdown and I can configure everything for it except for the placement compared to the other screens. For that I now have to use kscreen-doctor instead (which still works fine). STEPS TO REPRODUCE Not entirely sure how to reproduce, as it hasn't happened on any other system with multiple screens. OBSERVED RESULT Unable to re-arrange location of the TV. EXPECTED RESULT Able to re-arrange location of the TV. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Alpine Linux edge (available in About System) KDE Plasma Version: 5.27.5 KDE Frameworks Version: 5.106.0 Qt Version: 5.15.9 with KDE patches ADDITIONAL INFORMATION This has worked fine at least til 5.26 and I think it broke with the 5.27 upgrade but I'm unsure about it.
*** This bug has been marked as a duplicate of bug 459744 ***
I don't think it's the same, it's not just overlapping. You can drag the screens it _does_ show anywhere and the third screen will _never_ appear.
Oh ok. That's odd. So when you select the missing screen in the combobox, what happens in the draggable view?
Literally nothing. It doesn't indicate any screen, both other screens just get unselected.
How strange. Can you attach a screenshot that shows the KCM when it's in that state?
Marking as info required.
Created attachment 159508 [details] Screenshot of the Display Configuration KCM Attached the screenshot. As you can see the device selected in the dropdown isn't present in the "Drag screens" view.
Actually I just realized the right screen is marked as duplicated, so I guess that's where that screen is? That isn't in anyway clear though if you just select the screen from the dropdown. Also I'm unsure how to get it detached from that other screen. Screen priorities seems to do nothing
Yep, that's where it is. Is the right screen *actually* mirroring its content to another screen? OR is the KCM showing this erroneously?
No that part is correct, it's mirroring that screen. It's not what I want though, I actually want it to mirror my left screen and right now I have to run a kscreen-doctor command every time I turn that screen on.
Ok, I think we have two issues here: 1. The way mirrored screens is represented is confusing; see Bug 459744. 2. Your setup involves two screens mirroring each other, but this isn't what you want; you want one of the screens to mirror a *different* screen and you have to use kscreen-doctor for that, and when you do, the changes don't persist (how? Across what timeframe?) Is that accurate?
Yes that is accurate. The changes don't persist when I turn off and on that third screen. For some reason even though the screen is still detected when it's off, it's rearranges my screen setup and when I turn it back on it's back to mirroring the wrong one.
Ok, thanks. Let's mark this bug report as a duplicate of Bug 459744, since it's mostly about that. Can you submit a new one for the specific issue that your mirroring changes don't persist? *** This bug has been marked as a duplicate of bug 459744 ***
I'm still not sure it's the exact same as that report. Like I said it's not hidden, it's just not there. I can drag the "overlapping" screen all I want, the other screen _will_ _not_ _appear_. And the screen gives me no way to "detach" the screen either. In that other bug report it seems you can just drag the screens off each other and everything will appear correctly. I will file a report separately for the changes not persisting though, that indeed is separate.
There are apparently two ways that mirroring can be represented. One by simple overlapping, and another by the way they you're experiencing--with a little "we're mirrored" icon in the corner. This probably needs to be gone over from a UX perspective.