I have recently seen tags like <nowiki> and <pre> changed to UNIQsomethingQINU when saving edits. HEre are some diffs:
http://translatewiki.net/w/?title=Process%2Ftasks&diff=162097&oldid=162086
http://translatewiki.net/w/?title=User_talk:Siebrand&diff=prev&oldid=159497
Version: unspecified
Severity: normal