Firefox will block autoplaying audio in version 66 on March 19, 2019

Firefox is joining the ‘Don’t play audio until after the user clicks or taps’ team. If you haven’t already updated your autoplaying audio due to Chrome’s restriction on autoplaying audio, Firefox is giving you another reason to make sure you rely on user interaction before your audio plays:

Starting with the release of Firefox 66 for desktop and Firefox for Android, Firefox will block audible audio and video by default. We only allow a site to play audio or video aloud via the HTMLMediaElement API once a web page has had user interaction to initiate the audio, such as the user clicking on a “play” button.

Any playback that happens before the user has interacted with a page via a mouse click, printable key press, or touch event, is deemed to be autoplay and will be blocked if it is potentially audible.

Muted autoplay is still allowed. So script can set the “muted” attribute on HTMLMediaElement to true, and autoplay will work.

We expect to roll out audible autoplay blocking enabled by default, in Firefox 66, scheduled for general release on 19 March 2019. In Firefox for Android, this will replace the existing block autoplay implementation with the same behavior we’ll be using in Firefox on desktop.