Further to this, my sound stopped working. "No input/output devices detected."
Turned out if I went to the settings and turned on "show inactive devices", then changed the Profile from 'none' to 'Analog Stereo Duplex', it went back to normal and worked. sigh
That's what I get for a rolling release, I guess. I just hope the friends I set up on Linux Mint don't get similar issues, since I'm not around to help when things break.