Can't search for closed issues on a closed milestone
Let's say someone reports a bug that I think was fixed and closed on a released and closed milestone, and I need to search for it. I go to Milestones, select Closed, and click on the "NN issues" link under the closed milestone header. I see "No issues to show" because the default is to show the Open issues.
So I now click on Closed, but that sends me to all the closed issues, ignoring the milestone tag. Pull down on the Milestone tab and you only have the option to filter on open milestones -- you can't filter on closed milestones.
So two bugs I think: you should be able to filter on closed milestones on the bug search page, and when clicking on the Closed tab while viewing a milestone's bugs, you should go to a milestone-tagged closed bug list.
Proposal
Show open milestones as the default in the dropdown but allow ability to type a closed milestone and see it in the autocomplete from the issues page.