Default autoplay level
Supported on: Firefox 76 or later, Firefox 68.8 ESR or later
Registry
HKLM
Software\Policies\Mozilla\Firefox\Permissions\Autoplay HKCU
Software\Policies\Mozilla\Firefox\Permissions\Autoplay Options
Default enum - Allow Audio and Video
->
allow-audio-video - Block Audio
->
block-audio - Block Audio and Video
->
block-audio-video
Description
If this policy is enabled, you can choose the default autoplay level. If this policy is disabled or not configured, audio is blocked by default. Note: Blocking audio and video does not work on the ESR.