Hi Brian,we have a concept for this (not deployed beyond d a few test cases though).
We create a 'master' set of TC then reuse and synchronize them for the different deployments. Updates are made in the 'master' set and sync'd across as needed. Your 'browser tag' probably should be a field in the item type that's not synchronized so it can be maintained in each copy without showing 'out of sync'.
We then use the sync copy in test plans etc. I.e. there are never any test runs associated with the 'master' TC.
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