BEHAVIOR
This only seems to happen with a 4k monitor: when I let the display power off or turn off the screen, wait a bit, then turn it back on, the lock screen has a white background, pressing SPACEBAR doesn’t open the lock screen (left-click + drag with mouse does), and then after putting in the password, GNOME starts a new session instead of restoring the one I currently had (all windows that were open are now closed).
Which package should I file this bug under in Launchpad? gnome-shell? gdm?