Saved story tag feed URLs don't always have the tag name

If you right-click a saved story tag and go to “Tag Settings”, you get a dialog similar to the folder settings, but not the same. 

I would expect the url to always be in this format:{userId?}/{randomString?}/my-tag-name

But for some tags, it just gives a feed URL for all saved items (missing the tag name at the end):

I’d love it if that always gave valid tag feed urls, even for tags that were just created on the fly. So if I saved an item and tagged it with “foobar-baz”, it could come up here:

Then it could be consumed by IFTTT or whatever! Ignore the
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