Wikimedia Bugzilla is closed!

This *must* be a dupe, since I've seen the bug discussed more than once, but
slap me silly if I didn't search and search and I couldn't find a thing.  Bug
5382 is related, but not identical.

Anyway, the summary is fairly self-explanatory, but to clarify: if I add a
category to {{template}}, then pages that include {{template}} won't have the
new category until they (the transcluding pages) are edited.  Likewise, if I
remove a category, that too won't percolate down to the including pages.  This
is, of course, distinctly unexpected behavior, and should be fixed at some point.