Adding messages to a folder undergoing compaction should fail, and the calling code should deal with that failure in some sensible way. I'm reasonably confident that the former occurs, but not very confident of the latter.
Bug 274330 Comment 30 Edit History
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Adding messages to a folder should fail in the folder is undergoing compaction , and the calling code should deal with that failure in some sensible way. I'm reasonably confident that the former occurs, but not very confident of the latter. I'd be surprised if there _weren't_ some nasty corner cases lurking somewhere that still trigger this bug.