As a regular elog (ab)user, I have seen this behaviour from time to time.  So far as I recall, the cause actually is that a normal entry is looking for the entry in the "Reply to" field of the normal entry in the yymmdda.log file.  When that entry does not exist, then I see a duplicate line of an entry with entry "#0", in emboldened black type.  I did have a screenshot, but cannot find it for now. 

A quick (relative term, that) search usually finds the entry which references the missing "Reply to" line, and editing that, all is well.  I'm not sure how this can happen, but it does.  NB, I'm still on elog 2.9.2 so I don't know how the draft facility works and possibly enhances the possibility of this issue.

Note that this is different to the case (rather more frequent) where the entry in  the "In reply to" field is missing.  This causes elog to go into a continuous loop and only the strongest measures  ("kill -9 xxxx in linux) will break this out.  This can happen more frequently as if you delete a thread with a large number (>40?) of entries, elog crashes, but more importantly, hasn't finished the job.  Clicking on the remenents of the thread (which are usually the later entries) causes the endless loop.