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No h.264 playback on youtube

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When I try to enable html5 playback on youtube for most firefox browser. I find that h.264 playback is not allowed. Consequently I don't think I can play in 2x. I thought firefox natively adopted h.264 already. Am I mistaken?

When I try to enable html5 playback on youtube for most firefox browser. I find that h.264 playback is not allowed. Consequently I don't think I can play in 2x. I thought firefox natively adopted h.264 already. Am I mistaken?

Asịsa ahọpụtara

Do you have the codecs installed to play H.264 (MP4) videos?

On Windows XP you need to have the media.directshow.enabled set to true on the about:config page.

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Asịsa Ahọpụtara

Do you have the codecs installed to play H.264 (MP4) videos?

On Windows XP you need to have the media.directshow.enabled set to true on the about:config page.

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thanks. for whatever reason the problem resolved spontaneously. if i didn't have the codecs to play h.264 (mp4) videos would I have to install them manually? (i have some other computers that have this problem). Where would I get them? are they codecs for firefox or windows as a whole?

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out of curiosity i'm on a different computer running windows 7 and i have the same problem. i don't even see the option to enable the line you mentioned in about:config. How do i install the appropriate codecs?