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After recent update, Firefox displays MP4 incorrectly.

CMJillJones
CMJillJones
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I have a number of web courses I'm developing that until recently displayed perfectly fine. A few days ago, after a FF update, I opened one up in Firefox, and ALL of my MP4s are displaying with an enlarged and pixellated ghost of the video over the top. The color is wrong/obscured by the ghost, and it's really incredibly awful. I've tested on other systems, and everything seems fine, so I know it's something particular to this installation. I have uninstalled and reinstalled FF with no change in the behavior.

At this point, this is really more of a mystery than anything else, since I know the video is still functioning properly on other systems, but I would really appreciate understanding what has happened.

Thanks for any insight!

I have a number of web courses I'm developing that until recently displayed perfectly fine. A few days ago, after a FF update, I opened one up in Firefox, and ALL of my MP4s are displaying with an enlarged and pixellated ghost of the video over the top. The color is wrong/obscured by the ghost, and it's really incredibly awful. I've tested on other systems, and everything seems fine, so I know it's something particular to this installation. I have uninstalled and reinstalled FF with no change in the behavior. At this point, this is really more of a mystery than anything else, since I know the video is still functioning properly on other systems, but I would really appreciate understanding what has happened. Thanks for any insight!

All Replies (2)

Gingerbread Man
Gingerbread Man
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Do you have any example links to the MP4 files that can be tested?
Have you tried updating your video card drivers?
Have you tried disabling hardware acceleration?

CMJillJones
CMJillJones Question owner
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Hi there and thanks for the reply,

Unfortunately, I do not have any links I can share. The videos are proprietary, and what I have access to is local only. I could post a screenshot if that would be useful.

I haven't tried either of these solutions yet for a couple of reasons - the biggest one being that the videos look fine in IE and Chrome. It's only FF that is displaying the strange behavior, and they *used* to be fine in FF as well. Something, somewhere, broke.

I'm about to get a new system, so the issue will soon be moot. But I'll give the driver route a go tomorrow and see what happens. I honestly don't know enough to be able to tell if hardware acceleration is currently in use.