Try turning on auto play. Or try reloading youtube.

                     Hope you find this helpful.
                            lev-09

Make sure you are not blocking content.

Start Firefox in Safe Mode {web link}

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop

Hello   mace2,

Would you please go over this article   (especially the last part) :

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

Then, just to make sure, go to the about   "about:config"   page   (I don't have to tell you how cause you already know the drill) and make sure that the value of the preference : media.block-autoplay-until-in-foreground   is set to "false".

Also make sure that the value of the preference :
media.autoplay.enabled.user-gestures.needed   is set to   "false".

Any luck ?

Thanks you McCoy.

The problem I had was trying to make the selection while the video was playing. You must select the permission berfor the video starts. In my case youtube.

Thanks you McCoy. The problem I had was trying to make the selection while the video was playing. You must select the permission berfor the video starts. In my case youtube.

I'm glad you figured it out   -   enjoy your videos !

The solution works for Mac OS but does not work for Ubuntu mate. I performed the same operation selected autoplay "allow audio and video" but it does not place this in the permissions. This is version 76.01

Any idea why this occurs?

The ubuntu FF version saves the permission information but when FF is restarted the information is removed.

Since FF is included with Ubuntu is there a way to verify the installed version of FF?