Type about:config<enter> in the address bar. If a warning screen comes up, press the I Accept the Risk button. At the top of the screen is a search bar. Type media.autoplay

media.autoplay.default = 1 [0:Allowed; 1:Blocked 2:Prompt] media.autoplay.allow-muted = false media.autoplay.enabled.user-gestures-needed = false

For user-gestures-needed you can try false and true to see what works for you

Hello Vijay,

Your screenshot shows that you have the value of this pref set to "false":

media.block-autoplay-until-in-foreground

Maybe change it to true, and see how that works for you.

Would you also take a look at this article, please (if you haven't already) :

https://support.mozilla.org/en-US/kb/block-autoplay

Note that services.sync.prefs.sync prefs like the last pref in the screenshot set what prefs are part of Sync and set what prefs to sync to other connected devices.

You can leave this pref to default (true) since they have no local effect.

• services.sync.prefs.sync.media.autoplay.default