Self disabled when loading youtube.

I cant understand where, how to force opera to use My Hosts System File to filter sites.

Please, I think it is a horrible mistake

I just found I'm getting this script injected by itself.
It is a JS, what is it???

:root a[href^="http://www.uzunpenisler.com/?ref="], :root [href^="http://ads.glispa.com/"], :root a[href^="http://newtraffic.mobi/?i="], :root a[href^="http://clk.mobgold.com/click.php?"], :root 
...
/?utm_"], :root a[href^="https://syndication.dynsrvtbg.com/splash.php?"] { display: none !important; }