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Unable to play a youtube video in Firefox 52 (OK in Chrome).

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  • 2 have this problem
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  • Last reply by etsenberg

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Unable to play a video (https://youtu.be/6yKtUDoylYg) in Firefox (OK in Chrome). Previous videos from the same creator (as way as many others, too) play OK. My OS is XP SP3. Restarting in safe mode doesn't help. I find no way to turn off hardware acceleration in Options (there is no Performance in General!), but I switched media.hardware-video-decoding.enabled to false, that didn't help either. Anyway, everything works with the same video card and drivers in Chrome, as I've said. I installed Shockwave flash 26, but 25 is still shown in add-ons, and if I turn it to Never activate, 26 also disables. Here is the debug info: {

 "ns": "yt",
 "el": "detailpage",
 "cpn": "H9ZKv2kHhCUpIRRm",
 "docid": "6yKtUDoylYg",
 "ver": 2,
 "referrer": "http://yun.complife.info/apoems.htm",
 "cmt": "0",
 "plid": "AAVV-GlIZejg3flA",
 "ei": "AS6FWbTYOsTl-wXoyqv4Bg",
 "fs": "0",
 "rt": "78.76",
 "of": "GC6OCn1lTVgpgJyrp2hYjw",
 "euri": "",
 "lact": 1,
 "cl": "164088117",
 "mos": 0,
 "state": "80",
 "vm": "CAEQABgE",
 "volume": 23,
 "c": "WEB",
 "cver": "1.20170803",
 "cplayer": "UNIPLAYER",
 "cbr": "Firefox",
 "cbrver": "52.0",
 "cos": "Windows",
 "cosver": "5.1",
 "hl": "en_US",
 "cr": "US",
 "len": "221",
 "fexp": "9408098,9422596,9431012,9434289,9434326,9439833,9446364,9447854,9449243,9456997,9457141,9458231,9461945,9463594,9463829,9464484,9465813,9466793,9466795,9466797,9467217,9467503,9467504,9467507,9468797,9468799,9468805,9474594,9475678,9476492,9476559,9478523,9480475,9480775,9481684,9481687,9482097,9482165,9482647,9483178,9483508,9483848,9484236,9484706,9485999,9486508,9487592",
 "feature": "youtu.be",
 "vct": "0.000",
 "vd": "NaN",
 "vpl": "",
 "vbu": "",
 "vpa": true,
 "vsk": false,
 "ven": false,
 "vpr": 1,
 "vrs": 0,
 "vns": 0,
 "vec": null,
 "vvol": 0.23,
 "debug_error": {
   "errorCode": "fmt.noneavailable",
   "errorDetail": "nosupported.1;f18.1;f43.0",
   "message": "This video format is not supported.",
   "messageKey": "YTP_HTML5_NO_AVAILABLE_FORMATS_FALLBACK"
 },
 "ismb": 5710000,
 "relative_loudness": "NaN",
 "user_qual": "hd720",
 "debug_videoId": "6yKtUDoylYg",
 "0sz": false,
 "op": "",
 "yof": false,
 "dis": "",
 "cgr": true,
 "debug_playbackQuality": "unknown",
 "debug_date": "Fri Aug 04 2017 22:39:42 GMT-0400"

}

Unable to play a video (https://youtu.be/6yKtUDoylYg) in Firefox (OK in Chrome). Previous videos from the same creator (as way as many others, too) play OK. My OS is XP SP3. Restarting in safe mode doesn't help. I find no way to turn off hardware acceleration in Options (there is no Performance in General!), but I switched media.hardware-video-decoding.enabled to false, that didn't help either. Anyway, everything works with the same video card and drivers in Chrome, as I've said. I installed Shockwave flash 26, but 25 is still shown in add-ons, and if I turn it to Never activate, 26 also disables. Here is the debug info: { "ns": "yt", "el": "detailpage", "cpn": "H9ZKv2kHhCUpIRRm", "docid": "6yKtUDoylYg", "ver": 2, "referrer": "http://yun.complife.info/apoems.htm", "cmt": "0", "plid": "AAVV-GlIZejg3flA", "ei": "AS6FWbTYOsTl-wXoyqv4Bg", "fs": "0", "rt": "78.76", "of": "GC6OCn1lTVgpgJyrp2hYjw", "euri": "", "lact": 1, "cl": "164088117", "mos": 0, "state": "80", "vm": "CAEQABgE", "volume": 23, "c": "WEB", "cver": "1.20170803", "cplayer": "UNIPLAYER", "cbr": "Firefox", "cbrver": "52.0", "cos": "Windows", "cosver": "5.1", "hl": "en_US", "cr": "US", "len": "221", "fexp": "9408098,9422596,9431012,9434289,9434326,9439833,9446364,9447854,9449243,9456997,9457141,9458231,9461945,9463594,9463829,9464484,9465813,9466793,9466795,9466797,9467217,9467503,9467504,9467507,9468797,9468799,9468805,9474594,9475678,9476492,9476559,9478523,9480475,9480775,9481684,9481687,9482097,9482165,9482647,9483178,9483508,9483848,9484236,9484706,9485999,9486508,9487592", "feature": "youtu.be", "vct": "0.000", "vd": "NaN", "vpl": "", "vbu": "", "vpa": true, "vsk": false, "ven": false, "vpr": 1, "vrs": 0, "vns": 0, "vec": null, "vvol": 0.23, "debug_error": { "errorCode": "fmt.noneavailable", "errorDetail": "nosupported.1;f18.1;f43.0", "message": "This video format is not supported.", "messageKey": "YTP_HTML5_NO_AVAILABLE_FORMATS_FALLBACK" }, "ismb": 5710000, "relative_loudness": "NaN", "user_qual": "hd720", "debug_videoId": "6yKtUDoylYg", "0sz": false, "op": "", "yof": false, "dis": "", "cgr": true, "debug_playbackQuality": "unknown", "debug_date": "Fri Aug 04 2017 22:39:42 GMT-0400" }

Chosen solution

According to other users, YouTube recently dropped Flash formats, and now only uses an HTML5 video player. Firefox users on Windows XP are experiencing delays in when they can play new videos.

My theory on this is that the creator uploaded the video in a format that Firefox cannot decode on Windows XP (H.264/MP4) because Firefox requires the Microsoft Media Foundation and Microsoft only released it for Vista and later versions. However, Google transcodes videos to other formats in the background, so eventually a playable format becomes available.

There is a potential workaround for Firefox 52 Extended Support Release on Windows XP here (I haven't tried this myself): http://www.msfn.org/board/topic/175591-enable-mp4-h264-aac-html5-video-in-firefox-on-windows-xp-without-flash/

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Chosen Solution

According to other users, YouTube recently dropped Flash formats, and now only uses an HTML5 video player. Firefox users on Windows XP are experiencing delays in when they can play new videos.

My theory on this is that the creator uploaded the video in a format that Firefox cannot decode on Windows XP (H.264/MP4) because Firefox requires the Microsoft Media Foundation and Microsoft only released it for Vista and later versions. However, Google transcodes videos to other formats in the background, so eventually a playable format becomes available.

There is a potential workaround for Firefox 52 Extended Support Release on Windows XP here (I haven't tried this myself): http://www.msfn.org/board/topic/175591-enable-mp4-h264-aac-html5-video-in-firefox-on-windows-xp-without-flash/

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Thank you, manual installation of The Primetime CDM plugin requires a lot of action but solves the problem!