On Recentchanges, Watchlist, history and other places (I think MediaWiki calls them ChangesList), there are span elements with the class mw-usertoollinks that contain links. These links do not have any classes on them. This makes it unnecessarily difficult for users who want to want to do something with these links with CSS and/or JavaScript. You can't target them by text because users have different user languages. You can't target them by href or title because of different content languages. And finally, you can't target them by index because the contribs link for anonymous users is where the link to the user page is for logged-in users.
Related: T102013