Is it site specific? Does the video on the JWPlayer home page work?

http://www.jwplayer.com/

For me, the page uses a <video> tag to invoke the built-in HTML5 player, no plugin required. However, this presumably varies from browser to browser based on configuration.

Thanks jsher. The video on the JWPlayer does work. So the bug is the website I'm visiting to view the video, I presume? In Safari all is doing well.

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Hi aleid, thanks for testing that.

There might be an issue with the site, for example, not keeping up with changes in Firefox, or there might be a permission or extension setting in your Firefox that is blocking something needed to play the video. Often videos are hosted on different servers than the main web page, and information is transferred between the servers, so privacy-related settings (such as third party cookies) and add-ons (such as anti-tracking extensions) could be a factor.

Could you try the site in Firefox's Safe Mode? That's a standard diagnostic tool to bypass interference by extensions (and some custom settings). More info: Diagnose Firefox issues using Troubleshoot Mode.

You can restart Firefox in Safe Mode using

Help > Restart with Add-ons Disabled

In the dialog, click "Start in Safe Mode" (not Reset)

Any difference?

Hi jscher, it doesn't make any difference. I tried but the video won't play. In Safari however it does work.

Do you see an error message about this in the Web Console (Firefox/Tools > Web Developer;Command+Shift+K)?

Is there a shield or other extra icon on the left end of the location bar indicating that content is blocked?