Could you clarify what you mean by "everything on the desktop": icons, icons and panels, icons and panels and open programs?
You might check the log files for around the time you suspended the computer; perhaps you'll find something there. I don't have Mint right now, so I can't suggest particular logs and I know the *buntus have deviated slightly from tradition log names--perhaps /var/log/Xorg.0.log, /var/log/messages (or equivalent), and /var/log/syslog (or equivalent). (I'm pretty sure Mint has rsyslog installed to pipe SystemD logs to /var/log. If not,
this link will help.)
And no, I've never encountered anything like this.
