I've just released Mp3tag for Mac v1.8.22 with the following changes:
Changed, Improved & Fixed
- Renaming folders to nested subfolders via action Format Tag Field for
_DIRECTORYon multiple files was applied on already renamed folder in some cases. (#64628) - JSON-related functions
json_foreachandjson_foreach_endof Web Sources Framework reverted back to root object and not to previously selected object. (#64047)
It's a free update! You can update the Mac App Store version via the Update tab in the App Store app and the standalone version from within the app via File → Check for Updates .