On latest KDE Rawhide (to be 43), whenever the screen locks, the KScreenLocker crashes leaving a black and white where a workaround is described how to unlock the session manually.

While this happens, the following is logged:

```
        čen 30 12:44:37 localhost-live audit: BPF prog-id=58 op=UNLOAD
        čen 30 12:44:38 localhost-live systemd[1]: systemd-hostnamed.service: Deactivated successfully.
        čen 30 12:44:38 localhost-live audit[1]: SERVICE_STOP pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=systemd-hostnamed comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
        čen 30 12:44:38 localhost-live audit: BPF prog-id=59 op=UNLOAD
        čen 30 12:45:35 localhost-live kwin_wayland_wrapper[2545]: libEGL warning: egl: failed to create dri2 screen
        čen 30 12:45:35 localhost-live kwin_wayland_wrapper[2545]: libEGL warning: egl: failed to create dri2 screen
        čen 30 12:45:35 localhost-live kscreenlocker_greet[2545]: qml: The backend got an unknown wallpaper provider type. The wallpaper will now fall back to the default. Please check your wallpaper configuration!
        čen 30 12:45:35 localhost-live systemd[1001]: Starting grub-boot-success.service - Mark boot as successful...
        čen 30 12:45:35 localhost-live systemd[1001]: Finished grub-boot-success.service - Mark boot as successful.
        čen 30 12:45:35 localhost-live kscreenlocker_greet[2545]: file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockOsd.qml:10:1: "../osd": no such directory
        čen 30 12:45:35 localhost-live kernel: kscreenlocker_g[2545]: segfault at 149 ip 00007f1e47a1b19d sp 00007ffc158b7d40 error 4 in libLayerShellQtInterface.so.6.4.1[319d,7f1e47a18000+7000] likely on CPU 1 (core 0, socket 1)
        čen 30 12:45:35 localhost-live kernel: Code: be 02 00 00 00 4c 89 e7 31 c0 e8 2e da ff ff 49 83 7e 10 00 0f 85 8b 00 00 00 49 8b 87 b0 01 00 00 48 85 c0 74 32 4c 8b 63 18 <4c> 8b 70 18 44 8b 6d a8 4c 89 e7 e8 53 d9 ff ff 48 83 ec 08 31 d2
        čen 30 12:45:35 localhost-live audit[2545]: ANOM_ABEND auid=1000 uid=1000 gid=1000 ses=3 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 pid=2545 comm="kscreenlocker_g" exe="/usr/libexec/kscreenlocker_greet" sig=11 res=1
        čen 30 12:45:35 localhost-live audit: BPF prog-id=62 op=LOAD
        čen 30 12:45:35 localhost-live systemd[1]: Starting fprintd.service - Fingerprint Authentication Daemon...
        čen 30 12:45:35 localhost-live systemd[1]: Started fprintd.service - Fingerprint Authentication Daemon.
        čen 30 12:45:35 localhost-live audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=fprintd comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
        čen 30 12:45:36 localhost-live kwin_wayland_wrapper[2577]: libEGL warning: egl: failed to create dri2 screen
        čen 30 12:45:36 localhost-live kwin_wayland_wrapper[2577]: libEGL warning: egl: failed to create dri2 screen
        čen 30 12:45:36 localhost-live kscreenlocker_greet[2577]: qml: The backend got an unknown wallpaper provider type. The wallpaper will now fall back to the default. Please check your wallpaper configuration!
        čen 30 12:45:36 localhost-live kscreenlocker_greet[2577]: file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockOsd.qml:10:1: "../osd": no such directory
        čen 30 12:45:36 localhost-live audit[2577]: ANOM_ABEND auid=1000 uid=1000 gid=1000 ses=3 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 pid=2577 comm="kscreenlocker_g" exe="/usr/libexec/kscreenlocker_greet" sig=11 res=1
        čen 30 12:45:36 localhost-live kernel: kscreenlocker_g[2577]: segfault at 159 ip 00007f327f0f619d sp 00007ffc7b4e5f30 error 4 in libLayerShellQtInterface.so.6.4.1[319d,7f327f0f3000+7000] likely on CPU 1 (core 0, socket 1)
        čen 30 12:45:36 localhost-live kernel: Code: be 02 00 00 00 4c 89 e7 31 c0 e8 2e da ff ff 49 83 7e 10 00 0f 85 8b 00 00 00 49 8b 87 b0 01 00 00 48 85 c0 74 32 4c 8b 63 18 <4c> 8b 70 18 44 8b 6d a8 4c 89 e7 e8 53 d9 ff ff 48 83 ec 08 31 d2
        čen 30 12:45:36 localhost-live kwin_wayland_wrapper[2608]: libEGL warning: egl: failed to create dri2 screen
        čen 30 12:45:36 localhost-live kwin_wayland_wrapper[2608]: libEGL warning: egl: failed to create dri2 screen
        čen 30 12:45:36 localhost-live kscreenlocker_greet[2608]: qml: The backend got an unknown wallpaper provider type. The wallpaper will now fall back to the default. Please check your wallpaper configuration!
        čen 30 12:45:36 localhost-live kscreenlocker_greet[2608]: file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockOsd.qml:10:1: "../osd": no such directory
        čen 30 12:45:37 localhost-live audit[2608]: ANOM_ABEND auid=1000 uid=1000 gid=1000 ses=3 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 pid=2608 comm="kscreenlocker_g" exe="/usr/libexec/kscreenlocker_greet" sig=11 res=1
        čen 30 12:45:37 localhost-live kernel: kscreenlocker_g[2608]: segfault at 167 ip 00007fd3573f019d sp 00007fff0aa655a0 error 4 in libLayerShellQtInterface.so.6.4.1[319d,7fd3573ed000+7000] likely on CPU 0 (core 0, socket 0)
        čen 30 12:45:37 localhost-live kernel: Code: be 02 00 00 00 4c 89 e7 31 c0 e8 2e da ff ff 49 83 7e 10 00 0f 85 8b 00 00 00 49 8b 87 b0 01 00 00 48 85 c0 74 32 4c 8b 63 18 <4c> 8b 70 18 44 8b 6d a8 4c 89 e7 e8 53 d9 ff ff 48 83 ec 08 31 d2
        čen 30 12:45:37 localhost-live kwin_wayland_wrapper[2633]: libEGL warning: egl: failed to create dri2 screen
        čen 30 12:45:37 localhost-live kwin_wayland_wrapper[2633]: libEGL warning: egl: failed to create dri2 screen
        čen 30 12:45:37 localhost-live kscreenlocker_greet[2633]: qml: The backend got an unknown wallpaper provider type. The wallpaper will now fall back to the default. Please check your wallpaper configuration!
        čen 30 12:45:37 localhost-live kscreenlocker_greet[2633]: file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockOsd.qml:10:1: "../osd": no such directory
        čen 30 12:45:37 localhost-live kernel: kscreenlocker_g[2633]: segfault at 17a ip 00007fbc0340019d sp 00007ffc3b1828a0 error 4 in libLayerShellQtInterface.so.6.4.1[319d,7fbc033fd000+7000] likely on CPU 0 (core 0, socket 0)
        čen 30 12:45:37 localhost-live kernel: Code: be 02 00 00 00 4c 89 e7 31 c0 e8 2e da ff ff 49 83 7e 10 00 0f 85 8b 00 00 00 49 8b 87 b0 01 00 00 48 85 c0 74 32 4c 8b 63 18 <4c> 8b 70 18 44 8b 6d a8 4c 89 e7 e8 53 d9 ff ff 48 83 ec 08 31 d2
         
```

It looks like there is a problem with the wallpaper provider which leads to crash in kscreenlocker_greet.


Reproducible: Always

Steps to Reproduce:
1. Install Fedora Rawhide (KDE).
2. Update to the latest state-of-art.
3. Lock the screen -> see the crash.
Actual Results:
KScreenLocker crashes and a manual workaround must be used to unlock the session.

Expected Results:
KScreenLocker works normally and locks and unlocks the session just fine.