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No Video with Supported format and MIME type found

Dawid Dettlaff
Dawid Dettlaff
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No Video with Supported format and MIME type found is not allowing me to play videos on website.

No idea what's the cause of it, I've tried everything from internet tips how to solve this.

No Video with Supported format and MIME type found is not allowing me to play videos on website. No idea what's the cause of it, I've tried everything from internet tips how to solve this.

All Replies (4)

jonzn4SUSE
jonzn4SUSE
  • Top 10 Contributor
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Steps to replicate the issue and the site please.

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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Hi Dawid, if you run an unbundled version of Windows (in countries where the antitrust settlement prevents Microsoft from preinstalling media components), you need to add them on. See: Fix video and audio problems on Firefox for Windows N editions.

If your Windows already has those components, could you check the following test page. It's my copy of the old YouTube HTML5 support page. You should see all "supported" or "probably" entries. Are any of them not supported?

https://www.jeffersonscher.com/sumo/html5-video.html

Dawid Dettlaff
Dawid Dettlaff Question owner
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jonzn4SUSE said
Steps to replicate the issue and the site please.

Open Jira. Open any uploaded mp4 file.

On some versions of FF it works, on some it does not.

Bluejay Young
Bluejay Young
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I have encountered this error only on substack and only recently (last couple of months or so). I have Windows 10 Pro, Firefox 108.0.1 (64-bit) and I just cleared my cache and cookies, again -- disabled privacy badger and Ublock and I still can't run videos on substack.