Doesn't seem to be in the list of fixes for 3.1 (may not even be a bug)
If you start your room with your sword on an orb, it has immediate effect (i.e. all the affected doors are open/closed/toggled immediately).
The same is not true if you enter on a pressure plate. If you are standing on a pressure plate that opens an immediately adjacent door (and there's no other tile to step on) you have no choice but to leave the room (so it's not just a question of it being the normal atypical room entry behaviour- when eyes can't see you, bombs don't go off etc).
This seems to me to be unintended, after all, Beethro is standing on the pressure plate.
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