Kwin does not know what screen its on

Help
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After the update to 6.1 certain full screen apps and games have lost their ability to display on the “primary” screen (I use 4) or the screen its internally set to use.

Kodi, for example, is set to run on my large 46 in display and for the past 5 years has done exactly that without fuss. Now, however, even though its set to use screen 4, HDMI1-0, it seems to randomly appear on whatever screen it wants, except HDMI1-0. The only way I can convince it to open on HDMI1-0 is to create a desktop icon and open it from the desktop on HDMI 1. However the icon will not persist on the desktop either, and after a logout or reboot, appears on Screen three (DVI-I-1-1).

What is odd about this, is even though Kodi will open on random screens, it actually thinks its on screen 4 with the mouse pointer popping over to screen 4 with the custom kodi pointer enabled even though the app is not there.

This also happens with some regular KDE app, with them opening all over the place, or their dialogs opening up on a different screen from the app that spawned it. Certain games, particularly those encumbered with the EA app, are also all over the place, showing up on the wrong screen.

I use 2 dedicated NV GPUs, with GPU 1 running one HDMI (primary) and one DVI, and GPU2 also running one HDMI and one DVI. Due to Wayland not supporting NV multi-GPU mosaic, I am using X11.

All of this was working perfectly in 5.27, became a bit flaky with the update to 6.0, but now with 6.1 is a complete mess. Unfortunately the crash handler is also crashing.

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Edit - well, I thought I had it solved, but alas… I have not. Making some adjustments to the priorities list in the display manager resulted in things working after a reboot, but then after a second reboot, all the same problems are back.

no longer true>>>>

Well, typically, its only after posting the problem when something new to try occurs to me, and typically, its only after posting the problem and then thinking of a new solution, that the solution works. It was the fact that the Kodi icon keep moving when rebooting that clued me in.

It seems there is a conflict between the screen layout section and the screen priority section in the display manager. The physical layout left to right is:

GPU 1: Scrn 1 (dvi1 1280x1024 rotated vertical) and Scrn2 (HDMI1 1920x1080 Primary standard)
GPU 2: Scrn 3 (dvi2 1680x1050 rotated vertical) and Scrn 4 (HDMI2 1920x1080 standard)

The “priority” drop down listed the displays in the order of HDMI1 (primary), DVI1, DVI 2, HDMI2.

Physically though, the GPU or perhaps KWin seems to consider HDMI as a higher “physical priority” than the DVI, so the fact that the second HDMI was set to a lower software priority than the second DVI was causing the issue. Changing the the list to "hdmi1,dvi1, hdmi2, dvi2 " even though that is not the physical layout solved the problem.

Even Kodi now behaves again. Odd problem as it worked fine the old way for years.
<<<<< no longer true