Screen lock doesn't work after upgrade to 21.10

Hello.
I upgraded 21.04 to 21.10 and screen lock doesn’t work since then. Not using key combination (tried to change - no result); not via graphical menu; not after suspend. It just doesn’t work.
How can I fix this? This is a high security risk to me.
Thank you for your help!

$ ps aux | grep -i screensaver | grep -v grep
dbz        16926  0.0  0.0 238988  5200 ?        Sl   17:46   0:00 /usr/libexec/gsd-screensaver-proxy
dbz        17054  0.0  0.3 2661772 26904 ?       Sl   17:46   0:00 /usr/bin/gjs /usr/share/gnome-shell/org.gnome.ScreenSaver

You have both GNOME Shell and Budgie installed - I’m guessing you are running GDM3?

From the above some ideas. But in essence - GNOME made changes in 21.10 that breaks budgie. Upstream Solus also have noted this and their recommendation is either / or - not both should be installed. Don’t use GDM3 either if you use budgie.

GDM3 has been disabled in systemd but I’ve uninstalled it anyway.
Found temporary solution in post you proposed. Thank you so much!