I think i found it lol:
https://www.wowinterface.com/downloa...Interface.html
Too bad the link is unusable
and i cannot download it anywhere.
I know almost for sure because i recognise this:
http://www.wowinterface.com/download...yler-Xsai.html
I also found this UI, which is 95% similar to what i'm looking for, but i'm almost sure it's not this one:
http://www.wowinterface.com/download...SC&page=2#info