Firefox 66 to block automatically playing audible video and audio

There are some sites on which users want audible autoplay audio and video to be allowed. When Firefox for Desktop blocks autoplay audio or video, an icon appears in the URL bar. Users can click on the icon to access the site information panel, where they can change the “Autoplay sound” permission for that site from the default setting of “Block” to “Allow”.

Source: hacks.mozilla.org