Yes I can still reproduce the issue, but it happens when HIBERNATING, not suspending (not sure whether it has changed or whether I erroneously wrote "suspend" when reporting it).
The issue is even much worse than I thought: if you happen to have the external screen available and you do re-plug it after resuming from hibernation, the output to the external screen will appear but the system will be frozen and won't respond to mouse or keyboard input. You have to switch it off via hardware.
Yes I can still reproduce the issue, but it happens when HIBERNATING, not suspending (not sure whether it has changed or whether I erroneously wrote "suspend" when reporting it).
The issue is even much worse than I thought: if you happen to have the external screen available and you do re-plug it after resuming from hibernation, the output to the external screen will appear but the system will be frozen and won't respond to mouse or keyboard input. You have to switch it off via hardware.