Sure, start a test thread with three entries. Then edit the second entry perhaps two dozen times in a row. Sooner or later it will disappear. Perhaps also log the occasional edit (but not all of them). This is how I’ve lost three very long posts in the past two weeks.

I suspect the spam filter might have something to do with this phenomenon. Also, Iridus seems to have found some good temporary workarounds while it’s being diagnosed.