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I have the latest QuickTime plugin - why can't I play mp4 videos in Firefox (they play just fine in Chrome!)?

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  • Last reply by Ranger6

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Firefox v32.0.3 QuickTime plugin v7.7.5 - Firefox indicates this is the latest WinXP SP3 - yeah, it's an old computer, but it still works for some things!

The QuickTime plugin is set to Always Activate. I double-click the QuickTime plugin in the Add-ons Manager and I see video/mp4 (MPEG-4 media: mp4) in the MIME types section. I go to a website I created and none of the mp4 videos I also created display. All I see is a black box. If I insert an mp4 video into a page, I get the same black box and for a split second a MIME error message flashes onscreen. The MPEG-4 setting is checked in the MIME settings of the browser tab of my QuickTime player preferences. An mp4 video should display in HTML5 without issue. For example, my mp4 videos display just fine on my website when using Chrome. What am I missing with Firefox?

And speaking of Add-ons, why does the Firefox Add-ons Manager display the "Adobe Acrobat is known to be vulnerable and should be updated. Update Now" message when the Adobe Acrobat plugin is up to date?

Thanks for any help!

Firefox v32.0.3 QuickTime plugin v7.7.5 - Firefox indicates this is the latest WinXP SP3 - yeah, it's an old computer, but it still works for some things! The QuickTime plugin is set to Always Activate. I double-click the QuickTime plugin in the Add-ons Manager and I see video/mp4 (MPEG-4 media: mp4) in the MIME types section. I go to a website I created and none of the mp4 videos I also created display. All I see is a black box. If I insert an mp4 video into a page, I get the same black box and for a split second a MIME error message flashes onscreen. The MPEG-4 setting is checked in the MIME settings of the browser tab of my QuickTime player preferences. An mp4 video should display in HTML5 without issue. For example, my mp4 videos display just fine on my website when using Chrome. What am I missing with Firefox? And speaking of Add-ons, why does the Firefox Add-ons Manager display the "Adobe Acrobat is known to be vulnerable and should be updated. Update Now" message when the Adobe Acrobat plugin is up to date? Thanks for any help!

All Replies (4)

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You can try to set the media.directshow.enabled to false on the about:config page to disable the HTML5 media player. Firefox may not be using another plugin with this pref set to true and might not be able to play the MP4 video if you do not have support for such a media type on XP.

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Thanks, but I guess I'm not understanding your suggestion. I play mp4 videos on my XP computer all the time, with the QuickTime player, the HTML5 video player (via Chrome), and even Windows Media Player which doesn't recognize the mp4 extension!! I don't want to disable the HTML5 media player, I want to know what to do to get the HTML5 video player working in Firefox. Does Firefox really not support the HTML5 video player?

Like I said tho, I must be misunderstanding your suggestion.

Modified by Ranger6

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Ok, here's the deal. Firefox (for some unknown reason) has the HTML5 video player, but does NOT support .mp4 files. To get .mp4 files to work, you either need to use a plugin or include a .ogg file. (I think I'm starting to understand why you had a problem with QuickTime)

I've had issues with QuickTime as well, but I always thought it was a problem with the website. Videos on Apple.com don't play even with QuickTime installed, but I didn't think anything of it. If you need to play .mp4 videos in your browser, try using VLC Media Player. It supports literally any video/audio file, and has a nice browser plugin.

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Thanks, but again, I'm either missing something or Firefox is being finicky. I play videos on Apple.com just fine thru Firefox, so the QuickTime plugin is apparently working. Of course, I didn't try every video on Apple.com so it's possible I picked the few that worked. And with some serious massaging I've actually been able to get Firefox to play low resolution .mp4 videos. Videos rendered at 256x144 display in the HTML5 video player in Firefox. Videos rendered at resolutions greater than 256x144 do not display in Firefox. At least, these are the results I'm getting....I suspect others may be getting different results.

This isn't a file size thing because a 512x288 .mp4 video is actually less than 1/2 the size of the lower resolution 256x144 .mp4 video, and yet Firefox does not display a 512x288 .mp4 video.....again, for me anyway. This is beyond confusing, but thanks for the suggestions. You are correct - Firefox does NOT support .mp4 videos (most resolutions) in the HTML5 video player....for some unknown reason!