FINALLY this worked. The prior attempts to disable website audio autoplay via about:config settings only worked on my devices, but not my desktop. This plugin did the trick and eliminating a regular source of irritation. Thanks, Afnan!

Works perfectly, what are these people talking about?
I see people saying they miss the FlashStopper ext, this is a perfect replacement, Thank you!

This appears to work exactly as advertised. FF v. 63.0, macOS 14.0 ("Mojave")

So far, it works. We'll see.

Works with YouTube perfectly as well as any other site using HTML5.

It works great! Finally I have a way to prevent youtube videos from automatically playing. A bunch of addons that specifically say that they'll stop youtube from autoplaying don't work at all. Thank you so much for this addon.

Edit: Idk why a bunch of other comments are so negative when all the other addons I've tried are the "piece of garbage" addons.

Vielen Dank für das Addon. Genau was ich gesucht habe. Autoplay wird überall blockiert und auf Seiten wo ich es doch haben will (Yotube) kann ich es gezielt einschalten. Keine Probleme :)

Works on gazeta.pl

This add-on is an excellent add-on. It works flawlessly. Do try.

Works nicely. Blocks annoying videos from playing automatically when a page loads. If you want to see an example of an annoying video, check out Texas A&M's homepage: Without the extension (or with it disabled), you have to tolerate a full-screen background video of people walking through campus and a large flag, flowers, foliage and other stuff blowing in the breeze for what seems like an eternity. With the extension enabled, the first image is stopped in its tracks and the extension allows you to get down to the business of finding your way around the site. This extension allows the user to decide when to play a video, rather than leaving it to the whims of a website developer.

Love that it stops auto-play on sites that I've never visited before. Was very easy to allow Youtube to automatically play while everything else doesn't.

The first one I've tried that actually works!! Well since the old flash days that is. It actually blocks HTML5 video, transforming my browsing experience. Thank you so much.

Super w 100% polecam w końcu mogę ustawić przeglądarkę tak jak Ja sobie życzę, np blokowanie autoplay na onecie, a na youtube startuje. Nie ma też żadnych problemów z pracą działa tak jak powinno !!!!

This solved the problem pronto! And with no apparent "side-effects" on my system or on the websites.