Plasma 6.3.6 / Wayland: many apps not show on taskbar & WindowList

I’ve just upgraded to Debian 13 and decided to use plasma but it seems I’ve got a problem that several folks have had but seem to resolved differently. Plasma 6.3.6 with Wayland seems to drop several app icons off the taskbar and window list once the app is fully loaded. Even simple apps like the calculator does this.

But, it works on X11 !

I’ve purged the ./.cache, ./.config has been stripped down and cleaned up. I’ve got Icons-Only Task Manager & Windows List. Updates are updated, all to no avail.

Is there some config in wayland that would drop app icons off the taskbar ?