Well as @Zanna had said, there never existed such links natively, but I was using this fine userscript  
[SE Modifications][1]  
which is apparently broken (at least in my installation) right now.

Before switching to tampermonkey I was looking forn an easy way to transfer the userscripts and stumbled over
[Userscript works in Tampermonkey on Chrome but not in Greasemonkey on Firefox (Stack Overflow)][2], where I found
>Add before // ==/UserScript== on a new line:  
>// @grant          GM_addStyle

Thats all that was needed (strange how it worked until now...)


  [1]: https://stackapps.com/questions/2138/se-modifications-username-autocomplete-in-comments-inline-revision-source-a
  [2]: https://stackoverflow.com/questions/32957523/userscript-works-in-tampermonkey-on-chrome-but-not-in-greasemonkey-on-firefox