A user reported on IRC, that s/he was assuming that by clicking "Discard", only the selected entry would be discarded from the list, and thus had lost the data in another other entry that naturally also got discarded (since the action just cancels the recovery and drops everything). The suggestion is to disable the selection in the document list (which is highlighted and gets a border), to avoid that false impression.
I think, the problem is already tracked in bug 114508, including a mockup by Heiko.
Thanks, Regina! You are definitely right! *** This bug has been marked as a duplicate of bug 114508 ***