Yep, you are right, bug reports is a good way. I’m not enough qualified to create a meaningful report in this particular case. Nobody likes reports like “Something went wrong”. But anyway, it seems, that such bug report already exists: 488719 – Not able to screenshare, due to screensharing popup being blank.
As for me, I resolved a problem by upgrading pipewire to upstream version from pipewire-debian | Upstream Version of pipewire, wireplumber, roc-toolkit & blueman for debian/ubuntu
Perhaps it will help someone who lost the ability to share screen this week.