I haven't heard of this problem before. Your browser says it is version 54.0.1 (as modified by Waterfox) so if this affected everyone, I think there would have been a post on it in the past 10 weeks. Something odd is happening.

Could you test in Firefox's Safe Mode? In Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement? (More info: Diagnose Firefox issues using Troubleshoot Mode)

Urobolos said

Is there a way to add exceptions for the media.autoplay option? As if there were a way to code for something like media.autoplay.enabled = false for all except site: Pandora, Amazon Music

No. It's not a "permission" so it doesn't have site-by-site settings.

We have seen issues before with autoplay disabled where a script running on the website doesn't detect this properly. In that case you would have to click Play twice to start the video.

jscher2000 said

I haven't heard of this problem before. Your browser says it is version 54.0.1 (as modified by Waterfox) so if this affected everyone, I think there would have been a post on it in the past 10 weeks. Something odd is happening. Could you test in Firefox's Safe Mode? In Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem. If Firefox is not running: Hold down the Shift key when starting Firefox. If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart. Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh). Any improvement? (More info: Diagnose Firefox issues using Troubleshoot Mode) Urobolos said

Is there a way to add exceptions for the media.autoplay option? As if there were a way to code for something like media.autoplay.enabled = false for all except site: Pandora, Amazon Music

No. It's not a "permission" so it doesn't have site-by-site settings.

No change in safemode. Behavior is the same as regular mode.

cor-el said

We have seen issues before with autoplay disabled where a script running on the website doesn't detect this properly. In that case you would have to click Play twice to start the video.

Double clicking the play button starts the progress bar (not sure if that's the actual progress or a buffering indication in this situation), but the time counter doesn't change and no audio plays. Additionally clicking the button again seems to lock it into a "paused" mode and click play again has no effect.

Just realized I don't need a Pandora account to test this:

https://www.pandora.com/station/play/3713379784854834023

In Firefox 55, the Web Console shows:

[7:53:27:38] WARN Client/mediaElementHarness: The play method is not allowed by the user agent or the platform in the current context, possibly because the user denied permission.

I don't know whether this is something unique to how the player works on Pandora or affects all scripted play() commands.

You can show the built-in player controls, limited as they are, by running this script:

var player=document.getElementById('mediaelement_0'); player.setAttribute('controls', 'true'); player.setAttribute('style', 'position:fixed; bottom:1px; left:1px; height:40px; width:200px; z-index:1000; display:block;');

But hopefully a more convenient method will be found, or Pandora will find a workaround. Have you reported this problem to them?

I have sent a message to Pandora, I have not yet heard anything from them.

Here's a screenshot for the previous post.