As part of the migration to normalize change tags in the database, we will need to add code to read from the new change_tag_def table instead of change_tag’s ct_tag column (hidden behind $wgChangeTagsSchemaMigrationStage = MIGRATION_WRITE_BOTH for now).
This needs some work:
- ChangeTag class in core
- API modules in core
- ContentTranslation extension
- MediaWiki-extensions-FlaggedRevs extension
- OAuth extension