Members of the "oversight" group should be displayed as "oversighter" instead of "oversight" in lists such as Special:ListUsers/oversight .
To locally fix the issue on en.wikipedia.org, I have requested creation of the "MediaWiki:Group-oversight-member" page, but this may also be an issue for other MediaWiki installations.
https://en.wikipedia.org/wiki/Special:Diff/896758299
Possibly related, although apparently incorrect or still an issue: T109327
Change 509735 had a related patch set uploaded (by JJMC89; owner: JJMC89):
[mediawiki/extensions/WikimediaMessages@master] Update the member name for the oversight group to oversighter.
Please see the comments on the thread at https://en.wikipedia.org/wiki/Wikipedia_talk:Oversight#Request_for_creation where there is clearly NO CONSENSUS for this change, particularly as it does not actually fix anything that is an actual problem.
@Risker, I am very disappointed by this bureaucratic objection to a typo fix that is backed by a local policy and can easily be overridden by creating the page with any content that the enwiki community decides on in an RFC.
Well, given my core objection is that it isn't a typo ("oversight" is the name of the permission), and the RFC is asking for opinions on a different special page than you've asked to have changed in this task, I'm not sure we're really on the same page here.
Before the patch, I wasn't aware that this is a Wikimedia-only extension providing the text. I genuinely believed this to be a global error that the enwiki community was insisting on keeping. Neither is the case.
Change 509735 abandoned by Urbanecm:
[mediawiki/extensions/WikimediaMessages@master] Update the member name for the oversight group to oversighter.
Reason:
task is declined