As far as I'm concerned, this is the single most important addon available for Firefox. My tip for new users is to go through the Wiki instruction manual on the developer's Github page, and learn about "hard" and "medium" blocking modes, as well as dynamic vs. static filtering. If you're anything but the most basic of computer users, a medium/hard blocking mode will help you get more out of uBlock Origin. It's really not hard to accomplish.

I just wanted to say thanks for the great work, I really appreciate the plugin!

great !

good！

Lighter, more efficient, more powerful than other blockers. Long live uBlock Origin!

Jest bardzo skuteczny i jednocześnie działa subtelnie.He is very effective and simultaneously is acting subtle.

Прекрасное расширение....

Best ad blocker, I recommend this to everyone

Super

Even more powerful than Adblock, very good job!!!

Works fine, better than AdblockPlus.

Bloqué bien lespubs

Best anti-ads ever:)

Very useful, and very efficent

Perfektný doplnok.

Great for blocking malware sites , adds , pop ups and speeds up browsing , still using in 2019 , GOLD standard of must have add-ons !

The best, Thx devs

Really useful for blocking unwanted web fetches while I am inside any Internet Banking Secure sites Eg., block www.google-analytics.com and the same applies to the sharemarket logons, I dont NEED or WANT a facebook icon while I am doing business!!
Another use is browsing from behind the Great China Firewall. Many sites have facebook and google icon/links type "fetches", these cause pages never to complete, Eg., browsing Western news sites, or even StackExchange and GitHub.
As measured by WebMIn (visually) ...about 2.25Gig RAM Released by FireFox on an 8Gig Linux workstation.

Excellent, should come by default in every browser.