Looks like SysRq keys are not enable in your distro by default, don’t know the reason but Fedora kernel devs would known better than me.
Just for curious, did you installed some gnome extension recently? try this
grep -i gnome-shell /var/log/syslog* | grep -i exten
Yes, and Google captchas are the worsts of all of them.
I found Buster a while ago and works most of the times, it use the accesibility audio challenger to try to solve it using speech recognition. When it don’t work I found more easy to try the audio challenger, you just need to write the part that you understand and not all you hear, less picky than the images, still a pain in the ass