Hello all, thanks for the comments. It came when I updated to Firefox 33.1 together with it's exe.
Though the name given by SpyHunter is a bit diffent in the name. Here on Opera it is written: DDG , but on SppyHunter and in the searchbar of Firefox it was DDg , maybe a false clone or..., the path of DDg was also not findable where it would be according the path.

Thanks,
Chris.

Hi,

I did send this as a bug report but lost reply, so I mention it here again.
DuckDuckgo.com is a HIJACKER! I was on Firefox before I came back to Opera browser.
I was forced to delete permanently the Firefox browser because together with the update to version 33.1, each time
DuckDuckgo.com came together as a hidden. Every time when I did SpyHunter check, SpyHunter urged me to delete it, because I was told it is a Hijacker that lock others their pc, manipulate, go into data and all other stuff the user has got on his / her pc! Each time I unstalled Firefox and reinstalled it again, the hijacker DuckDuckgo.com is in it. So I quitted all there, lost all my saved data and stuff on Firefox and now I'm back here on Opera.
This DuckDuckgo.com is in the list of extensions on Opera, so I thought after the warning, the Opera team would take it out of the list, but I see it is not done.

Best regards,
Chris.