Desktop icons not shown anymore in SLE 15.4

Please move this one if there’s a more appropriate forum.

Applies to both SLES and openSuSE: after upgrading to SP4 (and also on a fresh install with SP4 media) desktop icons don’t get shown anymore on a Gnome desktop with “SLE Classic” scheme.
They do in fact get created in the “Desktop” folder but have no effect.
Years ago we could work around such an issue by enabling “show-desktop-icons” underneath “org.gnome.desktop.background”, but this doesn’t seem to help this time.
The behaviour is the same on SP4 FCS boxes and on fully patched systems.