Kaikki vastaukset (1)
What do you mean by 'remove'? Do you want to stop the website from ever loading? If so, there is this extension (which I haven't used).
https://addons.mozilla.org/firefox/addon/block-website/
You can also add the site to a content blocker or use a hosts file.
https://addons.mozilla.org/en-US/firefox/addon/ublock-origin/