Comment # 5 on bug 1222442 from Michael Pujos

Stefan, your package is not crashing (manually installed
xorg-x11-server-21.1.11-749.1.x86_64.rpm)

I have also switched to using to regular SDDM for troubleshooting with the
advantage of being dropped to the SDDM login when it crashes (rather than
having to hard reboot due to the issue I mentioned).

Here's the relevant crash lines in Xorg.0.log:

[   126.867] (EE) 
[   126.867] (EE) Backtrace:
[   126.867] (EE) 0: /usr/bin/Xorg.bin (xorg_backtrace+0x7e) [0x56165c485b8e]
[   126.868] (EE) 1: /usr/bin/Xorg.bin (0x56165c2af000+0x1df5f9)
[0x56165c48e5f9]
[   126.868] (EE) 2: /lib64/libc.so.6 (0x7f908e600000+0x41240) [0x7f908e641240]
[   126.868] (EE) 3: /lib64/libc.so.6 (0x7f908e600000+0x949ec) [0x7f908e6949ec]
[   126.868] (EE) 4: /lib64/libc.so.6 (gsignal+0x18) [0x7f908e641176]
[   126.868] (EE) 5: /lib64/libc.so.6 (abort+0xd9) [0x7f908e628917]
[   126.868] (EE) 6: /lib64/libc.so.6 (0x7f908e600000+0x297e8) [0x7f908e6297e8]
[   126.868] (EE) 7: /lib64/libc.so.6 (0x7f908e600000+0x9f3c7) [0x7f908e69f3c7]
[   126.868] (EE) 8: /lib64/libc.so.6 (malloc+0x2fe) [0x7f908e6a3cdc]
[   126.868] (EE) 9: /usr/bin/Xorg.bin (0x56165c2af000+0x13536d)
[0x56165c3e436d]
[   126.868] (EE) 10: /usr/bin/Xorg.bin (0x56165c2af000+0x140b8a)
[0x56165c3efb8a]
[   126.868] (EE) 11: /usr/bin/Xorg.bin (0x56165c2af000+0x4d707)
[0x56165c2fc707]
[   126.868] (EE) 12: /lib64/libc.so.6 (0x7f908e600000+0x2a1f0)
[0x7f908e62a1f0]
[   126.868] (EE) 13: /lib64/libc.so.6 (__libc_start_main+0x8b)
[0x7f908e62a2b9]
[   126.868] (EE) 14: /usr/bin/Xorg.bin (_start+0x27) [0x56165c2fca35]
[   126.868] (EE) 
[   126.868] (EE) 
Fatal server error:
[   126.868] (EE) Caught signal 6 (Aborted). Server aborting