I'm not sure why the other reviews are low, this works with the new YouTube dark theme. I haven't seen any thumbnail problems or stuttering. Latest Firefox version 59 stable.

Besides the fact that everyone has already pointed out about the thumbnails being gone. I have a different issue. Stuttering during video playback on any flash or html 5 video. Just to make absolutely sure it was this add on I first restarted firefox in safe mode, stuttering gone. Then one by one I disabled an add on until the stuttering and thumbnails returned. It was this one, please fix I really enjoy blocking certain youtube channels from my children.

Doesn't work at all.. turn it on and it blocks EVERYTHING.

It was a great add-on before. However, now it causes the thumbnails on the Youtube trending page to not appear.

Update: Reverting to Video Blocker 6.0 seemed to fix the problem

for the people that keep saying this is working now its not. this was once my favorite adon but after the update its crap. ive reinstalled it because the reviews said it was fixed. ive tried it on Firefox 58.02 and crome 64.0.3282.186. ive also tried it on 3 different laptops all with same results. it blocks some things but not all. mostly keywords fail. i get tired of getting rap music videos all the time, i rather put a pistil in my mouth then listen to that crap. or sports i get a lot of, i hate sports with a passion but here it is all over my page with flying colors no matter if i block channels or keywords or wildcards. i finally just gave up on this and youtube all together.

Works great on Quantum 58.0.2. An essential, easy-to-use tool to get rid of unwanted content on YouTube. Right click and block -- easy to use on Win 10 PC. Gladly and easily made a small donation.

Sucks

Use blocktube by amitbl instead.
This one was wonderful until 2019-03-22, when it started blocking all of the videos on youtube.
It has not been updated in three years.

Anoying popup with donations is anoying

Awesome tool for stop bullshit Youtube content.

Absolutely essential addon , works perfect , thank you.

После крайнего обновления плагин "сломался", скрыв абсолютно все видеоролики.

Could be better, but it'll do.

Version 5.2.6 Released Sept. 11, 2017 106.5 KiB this is working.

The latest version are not working at all. Great Extension by the way.

GOD BLESS YOU NIGGA FKIN SAVED MY LIFE BEST EXTENSION AFTER ADBLOCK CONGRATULATIONS

Thank you Thank you Thank you Thank you Thank you Thank you Thank you Thank you
Finally a way to block channels, it's sad that Youtube hasn't done it natively but that goes to show you just where their priorities are at.... revenue.

YouTubeの旧デザインにしていると機能しませんね。

新デザインで試すと機能しています。

for those who use firefox quantum: extension still works, but...

1. you have to switch to new youtube format/layout
2. maybe you will need to clear cookies that contain "google" and "youtube" from your browser first

i noticed that some parts of youtube server are different from the new layout so video blocker won't work on them, but if you're watching your favourite content, the right pannel with suggested videos will be filtered with video blocker rules, the same as with search results on the main page, so that means this extension is still useful.