...which results in broken thumbnails. See the comment at http://en.wikipedia.org/w/index.php?title=Wikipedia%3AFeatured_picture_candidates%2FBattle_of_San_Pietro&diff=248893878&oldid=248795326
Test files:
*[[Image:Battle of San Pietro.ogv]]
*[[Image:Scincus scincus.ogv]]
I used ffmpeg2theora 0.22 to transcode the latter video.
Version: unspecified
Severity: normal