Anybody who doesn't like/want/need the linkover tooltip in Firefox, might want to try the answer given to the question at this url:

https://support.mozilla.org/en-US/question…

They recommend you insert the code in userChrome.css, but it also seems to work fine as a Stylish userstyle. Your choice I guess.

"Status4Evar" is an extension that also does this, among many other things, but I didn't need the whole addon, just that one tweak.