If you accidentally remove the wrong tag (either using right click context menu "Remove" or Alt-Shift-R) on matched tracks, there seems to be no way to undo/fix that without completely removing those files and reloading and re-matching them from scratch.

When you have hundreds or thousands of tracks and albums loaded (and selected), having to discard all your edits and reload them from scratch can waste an incredible amount (sometimes hours) of a users time waiting for them all to be looked up and re-matched to recover from this.

I would propose that the "Remove" tag function should instead become a toggle "Remove/Restore" so this can be easily undone.  First time it removes that tag from all the selected tracks.  Done again, it restores the value that had been there previously.

This is similar to the "Use Original Values" function, except that rather than the original values from the file's tags, it restores the value that had been found from the online Musicbrainz lookups and that would have been written had the files been saved prior to the tag "Remove".