Last modified: 2013-10-23 18:17:26 UTC
When MediaWiki:pipe-separator contains ​ (zero-width space: code 8203) , Special:Contributions escapes and shows the code itself instead of the space. An example is http://translatewiki.net/wiki/Special:Contributions/Whym&uselang=ja where MediaWiki:Pipe-separator is "​|​". (although this wiki is 1.20alpha, I confirmed in the Wikimedia deployment wiki as well) Possibly other codes are affected by the same problem.
Note that it does this only for the sequence of messages which is (histlast)(pipe-separator)(histfirst) and not on the individual lines which are (diff)(pipe-separator)(hist) (Message sequences from uselang=qqx)
Just to add: * An obvious work around is not to use character reference by the numerical code, and use the character directly. This is not very useful when you want to zero-width space, however. * Some character references are not affected by this problem as seen in the English Wikipedia's configuration http://en.wikipedia.org/w/index.php?title=MediaWiki:Pipe-separator&action=edit, which uses and  .
(In reply to comment #2) > * Some character references are not affected by this problem as seen in the > English Wikipedia's configuration > http://en.wikipedia.org/w/index.php?title=MediaWiki:Pipe-separator&action=edit, > which uses and  . Right, in fact, I'm not sure *why* these are affected. From looking at the code,   is treated just like ​