KDE 5.x Dual Monitor - Kwin does not paint the second screen correctly then crashes

Nvidia GTX 560 using 390 Nvidia driver.

I am trying to use xeoma 19.4.22, (from http://www.felanasoft.com) which displays my five IP cameras on the second monitor, in a "tiled" format.

This works fine under KDE4 (4.14.8-13.el7) but I cannot get it to work with KDE 5.x

I have tried two linux distributions; SUSE LEAP 15.3 and Alma Linux 8.5
They both cannot display the cameras.

With KDE5 under SUSE Leap 15.3 only 1/4 of the screen starts up with the tiled displayed, but clicking on full screen causes the screen to go blank and the application to crash

With KDE5 (5.23.3-1.el8.x86-64) on Alma Linux, again only 1/4 screen lights up,
The cameras are not displayed and I get multiple notifications of kwin crashing then the top right quadrant disappears.

Thinking it was xeoma, I tried to run xclock instead to the second monitor, but get the same problem, only quarter of the screen lights up then kwin crashes.

I call the applications from the command line using DISPLAY=:1.1; ./xeoma.app
having identified DISPLAY 1.0 is my primary display on main monitor hence Display 1.1 is the second monitor.

According to journalctl

Code: Select all

Feb 27 16:14:10 new kwin_x11[14819]: Module 'org.kde.kwin.decoration' does not contain a module identifier directive - it cannot be protected from external registrations.
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5127:46: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5129:48: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5131:48: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5135:47: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5137:46: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5145:48: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5149:46: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5151:46: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5155:45: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:11 new kwin_x11[14808]: kwin_xkbcommon: XKB: /usr/share/X11/locale/en_US.UTF-8/Compose:5158:46: this compose sequence is a duplicate of another; skipping line
Feb 27 16:14:12 new /usr/libexec/gdm-x-session[4806]: KCrash: Application 'kwin_x11' crashing...


Any hints appreciated.

I had similar experience a while back, early to mid last year. I run multi GPU/XScreen (normally run 12 screens). Anything launched on an XScreen other than 0.0 would crash, freakout, smear like a locked up Win95 application...fun stuff. However when I tested this it was with Kubuntu and Debian based distros are often behind. Moving to Arch based (Garuda) and testing with currentish KDE this is fixed.

After a couple of weeks of trying to get this setup working
I gave up and moved to XFCE
Worked first time