Mutter optionally requires rtkit, but it's crucial for a good user experience, so I've made it hard required at runtime and thus had to drop loong and riscv keywords. Please see about keywording rtkit and then re-keywording mutter. If it works, the journal (at least with systemd) should have messages like rtkit-daemon[1901]: Successfully made thread 162537 of process 162489 owned by '1000' RT at priority 20. And if really wanting to check, then one of the gnome-shell threads should have realtime priority. I'm not 100% sure, but I think this could be checked with e.g. htop by configuring it to show userspace process threads and then switching to tree view (F5) and then looking through the gnome-shell threads and spotting one with "-21" PRI while most others are 20 or something.
riscv done
Test failures of mutter have nothing to do with keywording rtkit. If rtkit doesn't get keyworded and newer version of mutter RE-keyworded, I will simply drop loong from mutter and thus GNOME overall eventually.
