This https://addons.mozilla.org/en-US/firefox/addon/hide-unwanted-results-of-go/ addon was doing everything I wanted, but sadly it is not compatible with the new firefox quantum. I basically want to be able to add websites on a blacklist, so that they won't appear again when I use google search. This is not for parental control, and I want to be able to block a variety of websites of my choice. This is a very important feature for me, and I will consider downgrading firefox so that I will be able to download the above addon. If there is another solution I would be happy to hear it. I know this was supposed to be Google's job, but it would be great if you could help me out. Thanks.