The current version of Firefox now includes a builtin autoplay permission setting.

Older versions of Firefox had the advance configuration (about:config) preference media.autoplay.enabled which was later replaced with multiple preferences by media.autoplay.default and media.autoplay.allow-muted

The current version of Firefox now includes a builtin autoplay permission setting. (from page above): "The Block Autoplay feature will be turned on gradually during the Firefox version 66 release cycle, so some users may not see it."

Do not see a builtin autoplay permission setting in v 66.0.5. I see I am due for upgrade to v 67.0 Will it be in there? Well, I;ll see soon. Thanks for your response, Helped.

You can look at these prefs on the about:config page to see what settings work for you.

• 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.

See also:

• media.block-autoplay-until-in-foreground

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

• http://kb.mozillazine.org/about:config

dshand said

Do not see a builtin autoplay permission setting in v 66.0.5.

The name of the setting on the Firefox settings page has thrown some people off. It's the Block websites from automatically playing sound option.

You can also allow or block autoplay on a site-by-site basis using the website permissions menu.

For more information, please refer to Allow or block media autoplay in Firefox.

Ah ha, so there is still no way to prevent *videos* from playing automatically. Yes, it's nice to be able to block audio from playing, but why not a choice for videos, too? If that choice were available, I'd certainly use it, as I really don't like videos that start automatically. They're annoying, intrusive, and, well, really annoying.

GeneW said

Ah ha, so there is still no way to prevent *videos* from playing automatically. Yes, it's nice to be able to block audio from playing, but why not a choice for videos, too? If that choice were available, I'd certainly use it, as I really don't like videos that start automatically. They're annoying, intrusive, and, well, really annoying.

The name of the setting may be confusing, but the Block websites from automatically playing sound setting does indeed stop the actual video from playing, not just the audio.

As cor-el already mentioned above, the media.autoplay.allow-muted and media.block-autoplay-until-in-foreground preferences will also help to tighten the restrictions on what videos are allowed to autoplay.

Interesting, thanks, I've wondered if the "block audio" option was also blocking some videos, but it does not block *all* videos from playing automatically (Firefox 67.0 under Windows 10). And I'll add that the option name is not at all confusing - it says it will block audio! If it is meant to block video, as well, then it would be easy to fix that description in Options. The bottom line for me and others, too, is that it would be very convenient to be able to block video and audio from playing automatically.

GeneW said

The bottom line for me and others, too, is that it would be very convenient to be able to block video and audio from playing automatically.

With the media.autoplay.allow-muted and media.block-autoplay-until-in-foreground preferences both configured, you can pretty much block any video from automatically playing. There are a few instances where a video may still play, but I've found that to be pretty uncommon.

dshand said

I thought I read in a recent FF update a feature that would block unwanted videos from starting. Is there such a feature? (Prior to ver 66.0.5)

I am now up to ver. 69.0, and FINALLY see the option referred in first repl on 5/21/19. Thanks to all!