I disabled the workboard for MediaWiki-Internationalization. Now whoever clicks the tag receives an unhelpful and misleading error message:
This workboard has been disabled, but can be restored to its former glory.
The error message should not be displayed at the URL /tag/mediawiki-internationalization/ . This bug can be considered an extreme case of T89865.
The workaround is to manually make the workboard non-default at https://phabricator.wikimedia.org/project/144/panel/configure/ (a very unfriendly positioning too, as this has nothing to do with panels). This setting should be implied by the disabling of the workboard.
Examples of incorrect (partial) disabling (without applying the workaround):