uBlock Origin is seriously the best browser extension in existence. The UI might be a little outdated, but other than that, this is, in my opinion, the best and the only adblocker / content blocker you should have installed on your Firefox browser.

This is an incredibly useful and essential extension for Firefox. The built-in filters remove a lot of the things which are irrelevant to the web-pages you're viewing and the custom filters let you remove even more of them.

The best browser ever.

THANK YOU SO MUCH I DONT HAVE TO DEAL WITH BAD ADS ON YOUTUBE!!!

Blocks malicious tracking elements from being loaded. Mandatory install for the modern web.