I think I might have the same issue. I get the “Oh no! Something has gone wrong” screen after logging in to Gnome.
I’ve logged in with Plasma to see the journal and it looks like gnome is throwing core dumps during start. So it looks to be related to this topic
@Yochanan Disabling extensions with gsettings set org.gnome.shell disable-user-extensions true (done from Plasma) doesn’t help.