I was searching for tags with 'new' in them on SO, and discovered a tag
[new-] (1), which most likely doesn't belong. So I clicked through on it to see the question that's tagged with it. The URL I was taken to is https://stackoverflow.com/questions/tagged/new-.
The resulting list of questions is identical to the listing of questions with the tag
To find that single question, I have to use this URL: https://stackoverflow.com/questions/tagged/new--
This behaviour is also reproducible using the search box. Putting in '[new-]' results in the same list as if I had put in '[new]', and finally using '[new--]' I can find that single question.
Now, this isn't a huge deal because these tags need to be removed (right?), but this was not the behaviour I expected when clicking/searching. I also found
[init-] by coincidence -- how many others are like this?