It won't stop videos from autoplaying, but your ears will catch a break by default with the release of Firefox 66 in March.
Mozilla , the nonprofit foundation behind the Firefox browser, announced Monday that it's improving your surfing experience a little by blocking autoplaying sound by default, rather than as a site-by-site opt-in.
Chris Pearce, a Mozilla software engineer, blogged that with the arrival of Firefox 66 for desktop and Android, the browser will silently autoplay videos when you open a web page. Currently you have to click on a speaker icon in the tab when the audio begins or right-click and choose "mute tab." (Here's how to mute in most browsers.)
You'll be able to listen to the video, but you will have to interact with the player, Pearce clarified. For sites such as YouTube, where it thinks people always want to listen to autoplaying video, Firefox gives you the ability to always allow audio from automatic playback. To activate it, you click an icon in the navigation bar and change the permission from block to allow.
Silence becomes golden when Firefox 66 arrives on March 19.