Leaving an editor whose access is gone uses the usual exit guard again:
it offers Leave anyway for work safely on this device and holds
otherwise. Discard drops an upload only when no change left on this
device places it, through the media queue's own reference check, so an
image whose placement is still being sent stays, and nothing is
blacklisted. Any failure while discarding still leaves, and says so.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>