Caused by rEABF extension-AbuseFilter's extension.json:

"suppress": {
     "abusefilter-hidden-log": true,
     "abusefilter-hide-log": true
   }
},

It has created a suppress group on MediaWiki which overlaps with the functions of the oversight group on MediaWiki.

While probably oversight is a Wikimedia-specific user right other MediaWiki installs do not use, in Wikimedia it's just causing confusion and it's moot.

Can we please deactivate this for WMF wikis? The rights suppress has are already included in the oversight group. See https://meta.wikimedia.org/wiki/Special:ListGroupRights.