FF58.0.2 x64
Doesn't work on certain pages. Options appear twice.
High cpu usage (25%) with this addon on certain pages (tested with only one tab and clean profile), even if video isn't playing.
Better set media.autoplay.enabled to false and change if needed with this bookmarked: about:config?filter=media.autoplay.enabled

XML files do not display properly when this extension is enabled

Most of the time doesn't work.

Does not work in Netflix.

I can't disable totally for a single url

Buggy. Options don't change with mouse clicks, appear twice and have no effect.

не работает

Don't work.

This blocks a lot of videos, and even entire channel pages, from loading in YouTube. Even if you tell it to not block anything on the page you are on, it still prevents them from loading. I am disabling this addon for now, I will remove it entirely if it isn't updated in a timely manner to not do this in FF 57.

it's a stupid addon,if you let it on,it stop the player when you click the play button over and over

Fait bugger beaucoup de choses, à commencer par les vidéos elles-même et rends les userScripts (via GreaseMonkey) totalement inutilisables.

Doesn't seem to prevent autoplay at most sites. Not even at big sites like Youtube - you'd think that it would be the first place to test an add-on like this, but oh well.

Can't play videos at all with the add-on enabled now.

BLOCK TWITCH FROM AUTOPLAY VIDEO BUT THEN I CANT START THEM...

it doesnt do anything at all

Can`t play youtubes video. It even block play button!

It simply doesn't work with the BBC News site. I've removing this pile of junk!

Use the built-in feature in Firefox instead:

1. Type about:config in the address bar and hit Enter.
2. Accept the warning to continue.
3. Search for media.autoplay.enabled and change the value to false by double-clicking on the row.

Enjoy your much better solution all through a built-in feature!

Installed it, tried to test at this link:
http://money.cnn.com/2017/07/18/news/economy/obamacare-trump-fail/index.html

And guess what? The adds autoplayed, the video autoplayed. The add-on simply doesn't work.

I found these instructions and they work. You can disable HTML5 autoplay natively without an add-on.

http://www.pcworld.com/article/3119886/software/stop-html5-autoplay-videos-in-chrome-firefox-opera-but-not-edge-explorer-safari.html

Does not prevent autoplay on TV GUide

Go over to the huffington post's website and load any page. It will autoplay even with this enabled.