The original report stated:
"I located a bear trap as a human and just ignored it
for the time. I polymporphed into a Vampire Lord, then
went to #untrap the bear trap. On the first attempt,
I stood beside the trap and attempted to #untrap. I
received the 'Whoops!' message and automatically moved
onto the trap square as a result. The bear trap vanished!
I obviously wasn't trapped since I'm polymorphed into a
flying monster, but the trap glyph was no longer present.
The glyph looked like regular floor - as if I had
untrapped the bear trap and taken the trap with me."
The trap was actually still there but became hidden intentionally
for other valid scenarios, but was an unintended side-effect for
this scenario.
Fix it by failing the #untrap operation for a Flyer earlier on,
and in a more benign manner, since the Flyer ultimately doesn't
end up in the trap anyway. You'll still get the "Whoops!",
followed by a message, but that's as far as the "failed" #untrap
attempt will go under the circumstances.
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