09:45, 19 December 2014 95.83.250.212 (talk) Comment text edited
linking a diff which says "no difference": this is not possible, null edits are not saved. Problems:
- &oldid= is empty and &diff=1248510 is probably incorrect (should be the opposite), because https://www.mediawiki.org/wiki/Special:Contributions/71.227.219.170 thinks that's the ID of the original comment: https://www.mediawiki.org/w/index.php?title=Thread:Help_talk:CirrusSearch/why_is_google_better&oldid=1248510 ;
- https://www.mediawiki.org/wiki/Special:Contributions/95.83.250.212, https://www.mediawiki.org/wiki/Special:DeletedContributions/95.83.250.212 and https://www.mediawiki.org/wiki/Special:Log/95.83.250.212 think that the user did not, in fact, do anything on the wiki.
So the "comment edited" link is not smart enough when it can't find the second revision; and either LQT history lies, listing an edit which doesn't exist, or we have some serious issues with partly saved edits which don't turn up in revisions nor logs.
Cf. T26039: History link on replies in thread namespace is rather broken. which is about *reply* history.