Steps to replicate the issue (include links if applicable):
- Don't be an interface administrator on enwiki
- Go to https://en.wikipedia.org/w/index.php?title=MediaWiki:Gadgets-definition&action=watch (works for any page which requires "editsitecss, editsitejs" permissions to edit)
- Regular users might end up here, if they open the link of the watchlist star icon in a new browser tab (middle mouse click, Ctrl+click, etc), or if they click the icon (or press the corresponding accesskey) sooner than JS code for handling the watchlist icon clicks without page loads is loaded.
- Another example: https://en.wikipedia.org/wiki/User:Ahecht/Scripts/refresh.js?action=watch
What happens?:
Permission error
This interface message or skin forms part of the MediaWiki interface. It may be documented on MediaWiki.org or translatewiki.net.
Only administrators and interface editors can editmywatchlist it. You can submit an edit request by clicking the button below and following the instructions.
(emphasis mine)
The error comes from:
- for MediaWiki page: https://en.wikipedia.org/wiki/MediaWiki:Protectedinterface
- for user's js page: https://en.wikipedia.org/wiki/MediaWiki:Customjsprotected
What should have happened instead?:
A form should load:
Update watchlist
Watchlist time period:
Permanent ⌵
Watch
This can be seen for other pages, even sysop-protected, like https://en.wikipedia.org/w/index.php?title=Main_Page&action=watch
Other information (browser name/version, screenshots, etc.):
action=unwatch is also affected: