Videos won't play in Nightly 的最新解答https://support.mozilla.org/zh-TW/questions/12806962020-02-27T11:09:35-08:00I switched to Nightly in order to watch videos because the version of FF that I had installed would 2020-02-27T11:09:35-08:00vhradicehttps://support.mozilla.org/zh-TW/questions/1280696#answer-1293990<p>I switched to Nightly in order to watch videos because the version of FF that I had installed would not play videos. I have since updated my default FF and it now plays videos. Now tha I can watch videos in the installed version, I will stop using Nightly. To me the problem has been solved - stop using Nightly. I don't know what you intend to do with this thread but I will not be watching it any more.
</p><p>Close it as unsolved if you want.
</p><p>Vincent Radice
</p>Do you check that you have current libavcodec packages/libraries installed ?
Do these videos pl2020-02-27T01:54:48-08:00cor-elhttps://support.mozilla.org/zh-TW/questions/1280696#answer-1293788<p>Do you check that you have current libavcodec packages/libraries installed&nbsp;?
</p><p>Do these videos play in other Firefox versions like release and beta&nbsp;?
</p>
<hr>
<p>You can create a new profile to test if your current profile is causing the problem.
</p><p>See "Creating a profile":
</p>
<ul><li><a href="https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles" rel="nofollow">https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles</a>
</li></ul>
<p>If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.
</p>
<ul><li><a href="https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile" rel="nofollow">https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile</a>
</li></ul>I tried to find libavcodec and it is not available as a separate package. From what I found it is i2020-02-26T18:34:43-08:00vhradicehttps://support.mozilla.org/zh-TW/questions/1280696#answer-1293718<p>I tried to find libavcodec and it is not available as a separate package. From what I found it is included with ffmpeg
</p>I'm not seeing libavcodec listed.
https://www.ffmpeg.org/libavcodec.html
https://www.google.com/sea2020-02-25T14:08:48-08:00cor-elhttps://support.mozilla.org/zh-TW/questions/1280696#answer-1293408<p>I'm not seeing libavcodec listed.
</p>
<ul><li><a href="https://www.ffmpeg.org/libavcodec.html" rel="nofollow">https://www.ffmpeg.org/libavcodec.html</a>
</li><li><a href="https://www.google.com/search?sa=N&amp;num=100&amp;q=libavcodec" rel="nofollow">https://www.google.com/search?sa=N&amp;num=100&amp;q=libavcodec</a>
</li></ul>I have the latest versions installed. Here is the dnf info on the packages referenced.
root@Vince2 2020-02-25T13:13:43-08:00vhradicehttps://support.mozilla.org/zh-TW/questions/1280696#answer-1293400<p>I have the latest versions installed. Here is the dnf info on the packages referenced.
root@Vince2 vince]# dnf list ffmpeg*
Last metadata expiration check: 0:01:12 ago on Wed 26 Feb 2020 12:07:11 AM EST.
Installed Packages
ffmpeg.x86_64 1:4.2.2-3.fc30
ffmpeg-libs.x86_64 1:4.2.2-3.fc30
Available Packages
ffmpeg-devel.i686 4.1.5-1.fc30
ffmpeg-devel.x86_64 1:4.2.2-3.fc30
ffmpeg-libs.i686 4.1.5-1.fc30
ffmpegthumbnailer.i686 2.2.2-2.fc30
ffmpegthumbnailer.x86_64 2.2.2-2.fc30
ffmpegthumbnailer-devel.i686 2.2.2-2.fc30
ffmpegthumbnailer-devel.x86_64 2.2.2-2.fc30
ffmpegthumbs.x86_64 18.12.3-1.fc30
[root@Vince2 vince]# dnf list libav*
Last metadata expiration check: 0:01:45 ago on Wed 26 Feb 2020 12:07:11 AM EST.
Installed Packages
libavc1394.i686 0.5.4-10.fc30
libavc1394.x86_64 0.5.4-10.fc30
libavdevice.x86_64 1:4.2.2-3.fc30
Available Packages
libavc1394-devel.i686 0.5.4-10.fc30
libavc1394-devel.x86_64 0.5.4-10.fc30
libavdevice.i686 4.1.5-1.fc30
</p>Make sure you have the latest FFmpeg/libavcodec packages installed.
2020-02-25T11:49:32-08:00cor-elhttps://support.mozilla.org/zh-TW/questions/1280696#answer-1293381<p>Make sure you have the latest FFmpeg/libavcodec packages installed.
</p>Nightly worked for a while but recently quit. I just now restarted Nightly as it had been updated. 2020-02-25T11:29:56-08:00vhradicehttps://support.mozilla.org/zh-TW/questions/1280696#answer-1293376<p>Nightly worked for a while but recently quit. I just now restarted Nightly as it had been updated. I tried a Youtube video and it would not play. I opened Help in Nightly and took a screenshot of the error message and the version of Nightly. It is attached.
</p><p>Opened Web Console and here is the error message from it
</p><p>Cannot play media. No decoders for requested formats: video/webm; codecs="vp09.02.51.10.01.09.16.09", video/mp4; codecs="avc1.42001E", video/webm; codecs="vp9", audio/mp4; codecs="mp4a.40.2", audio/webm; codecs="opus", video/mp4; codecs="avc1.42001E mp4a.40.2" watch
</p><p>Web page causing problem
</p><p><a href="https://www.youtube.com/watch?v=2OhndNJYnbc" rel="nofollow">https://www.youtube.com/watch?v=2OhndNJYnbc</a>
</p>Does this happen with all videos or does the YouTube website work ?
Does the Web Console show m2020-02-25T08:14:22-08:00cor-elhttps://support.mozilla.org/zh-TW/questions/1280696#answer-1293335<p>Does this happen with all videos or does the YouTube website work&nbsp;?
</p><p>Does the Web Console show media related messages&nbsp;?
</p><p>Can you post a link to a publicly accessible page (i.e. no authentication or signing on required)&nbsp;?
</p>