Thanks for your time and effort...much appreciated.

I couldn't get it to work after following your steps.

Here is what I did:

1. about:preferences#privacy >Tracking Protection >Never 2. about:config 3. media.autoplay.default > set to 2 4. went to metacritic.com, loaded a trailer, waited, then gave popup notification permission for autoplay.

I must be doing something wrong, since it worked for Roland Tanglao.

I'll keep using Chrome and Edge or Firefox 62.0.3 until a version of Firefox works on metacritic.

Thanks to all who helped out.

If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block (wanted) content (Adblock Plus, NoScript, Disconnect, Ghostery, Privacy Badger, uBlock Origin) always make sure such extensions do not block (wanted) content.

• make sure your extensions and filters are updated to the latest version
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

Firefox shows the shield icon at the left end of the location/address bar in case Content Blocking is blocking content.

• click the shield icon for more detail and possibly disable the protection

You can check the Web Console about what content is blocked

• "3-bar" menu button or Tools -> Web Developer
• https://support.mozilla.org/en-US/kb/tracking-protection
• https://support.mozilla.org/en-US/kb/content-blocking

Thanks "cor-el"

But we already addressed your suggestion earlier in the discussion.

I have no extensions enabled and content blocking (Tracking Protection) is off.

Firefox 64.0 works now on Metacritic.

Thanks to all for taking time to help.