Last modified: 2013-11-25 11:14:54 UTC
This null edit to an article (https://en.wikipedia.org/w/index.php?title=List_of_Sam_%26_Cat_episodes&diff=562710419&oldid=562703260) made the category hidden inside of a template in use on the page (template in question: http://en.wikipedia.org/wiki/Template:Episode_list) visible in the editor. It should not be visible.
Another example: https://fr.wikipedia.org/w/index.php?diff=94601807
This was a bug in DM/Parsoid interaction that we fixed months ago; apologies for the slowness of updating.