Step 1: Browse to http://stackoverflow.com/questions/tagged/ruby?sort=featured&pagesize=50.
Step 2: Browse to http://stackoverflow.com/questions/tagged/mediawiki.
This results in:
You are on the Featured tab. There are no questions with an active bounty at the moment. Perhaps you'd like to select a different tab?
Only thing is, there are no tabs shown, so it's not possible to do so and actually view any questions for the tag in question!
Apparently it's remembering that I'd last used the Featured tab for [ruby], and it defaults to that for [mediawiki] as well, and then blows up because there are no bounties for it. Oops?