sddm-greeter needs execution rights at /var/lib/sddm/.cache/sddm-greeter/qmlcache/*.qmlc
krunner needs execution at /home/user/.cache/krunner/qmlcache/*.qmlc
It breaks when /var and /home partitions are mounted with noexec flag which is often used on hardened setups or Trusted Path Execution available on hardened linux kernels.
As for now it could be fixed by disabling qml cache by setting QML_DISABLE_DISK_CACHE=1 environment variable.
Is there a chance that qt will check permission rights first then quietly disable qmlcache per app instead of crashing?
Alternatively it could create cachedir somewhere in /usr/lib/qt same as python3 have it's pycache dir.