No, I haven't installed a new desktop environment. I can think of only two
changes I made shortly before the problem began.
(1) Installing Thunderbird and making the mistake of letting it download all
of my emails, which took up all of my remaining disk space. I'll delete these
once I can log in again.
(2) I set up my printer. The printer worked during the first session I tried
it, but the next time it did not. I don't see how that could be related to
the problem, but the problem did begin when I restarted my computer to try to
get the printer working.
Yes, WiFi works with guest.
All important data is backed up, so as a last resort I'd be willing to
reinstall Trisquel, although I'd rather learn how to address the problem in
case it happens again.
A photo of the splash screen is attached.
Thanks so much for your help. I appreciate the time you're putting into this.
