"Three times in a row, after resuming from suspend I unlock the computer. Then immediately after unlock the screen goes black and then the login window again, forcing me to login yet another time.
Related or separate bug?"
I think that it is a clash between action on suspend (Settings -> Power) and action when inactive (Settings -> Brightness & Lock). I had suspend after 5 minutes and turning off screen after 5 minutes. I believe that this was causing duplicated unlock
"Three times in a row, after resuming from suspend I unlock the computer. Then immediately after unlock the screen goes black and then the login window again, forcing me to login yet another time.
Related or separate bug?"
I think that it is a clash between action on suspend (Settings -> Power) and action when inactive (Settings -> Brightness & Lock). I had suspend after 5 minutes and turning off screen after 5 minutes. I believe that this was causing duplicated unlock