Best demonstrated with a screenshot:
Pretty sure there were less of them earlier. The question itself has just the single annotation.
This was related to a recent change I made to question titles...
... and the problem was caching*, always caching!
On the home page, we cache a list of recent question objects in ASP.NET's HttpRuntime.Cache, which subsequent requests will use to render your interesting questions.
These question objects have a
NiceTitle property that will append those [closed], [duplicate], [migrated] status suffixes, and the code went something like this:
var suffix = GetQuestionStateSuffix(); if (suffix.HasValue()) Title += " " + suffix; return Title;
This worked fine in testing; the homepage looked as beautiful as ever. It looked beautiful because none of the normal homepage code used this
Mobile, on the other hand, does use it. And this is where the intermittent bug came in. Those cached objects kept getting their
Title happily overwritten each time a mobile user rendered a closed question's summary.
The fix is in and deployed - totally my bad.
* and a misguided assignment statement :)
** please don't ask why every rendered Title isn't done through NiceTitle... please.