Forum der Gemeinschaft Firefox

Please provide clear, step-by-step troubleshooting instructions to identify the cause of the problem and explain how to fix it. If possible, include the Firefox settings I should check and any tests I can perform to determine whether extensions, hardware acceleration, graphics drivers, or network settings are responsible.

I'm running the latest version of Firefox on the latest version of Windows 11, and I'm trying to watch TV shows on PBS's Passport service. I get the video but not the sound. It's been like this since Saturday. I don't have this problem at all with Chrome or Edge. Is anyone else having this problem? JT

Videos autoplay using iPad Pro M5 despite Auto-Play Video Previews, Auto-Play Animated Images and Auto-Play Message Effects all being turned OFF. Current Mozilla advice appears to be associated with PC use not iPad. Thank you!

I think everyone knows how to get out of full screen mode by now, so can you either remove it or let us disable that little box that always shows when you go full screen for a video?

Fire fox is automatically playing videos/sound or both if I click on a tab that has that or also in facebook, etc. How do I stop this? I want to be able to click play when I want to hear/see something.

Media resource could not be decoded, error: Error Code: NS_ERROR_DOM_MEDIA_DECODE_ERR (0x806e0004) Details: virtual mozilla::MediaResult mozilla::FFmpegVideoDecoder<62>::DoDecode(mozilla::MediaRawData*, uint8_t*, int, bool*, mozilla::MediaDataDecoder::DecodedData&): avcodec_send_packet error: Unknown error occurred

When I full screen in YouTube, Firefox makes a Fade in animation. Can I disable it and make the default animation works?

Note: I notice that Firefox on Linux doesn't have this feature, I don't know why this feature is only for Windows.

System Information: Surface laptop has Windows 11.

I couldn't sign my Alejandra .com on my computer so i need to cahnge to Firefox aboutpreferences@tabsBrwosing so the video from Aljazeera video live news awork on my computer Thank kind regards Peter tan

Quality switches to 360 when tab inactive firefox. I watch Twitch in 1080p. When I switch to another tab and then return, the quality drops to 360p and then automatically goes back to 1080p.

(AI written summary of troubleshooting steps taken before making this support thread)

Firefox version: - 152.0.1 Release - 153.0 Nightly

OS: - Windows 11 build 26200

GPU: - NVIDIA GeForce RTX 4070 SUPER

Codec package: - Microsoft HEVC Video Extensions installed from Microsoft Store

Problem

Firefox does not expose HEVC playback support, causing Twitch to disable 1440p streams encoded with HEVC.

The same machine can play the same HEVC Twitch streams in Chrome immediately after installing HEVC Video Extensions.

Expected result

Firefox should report HEVC playback support and allow playback of HEVC streams, as Chrome does on the same system.

Actual result

Firefox reports HEVC as unsupported.

about:support:

codecSupportInfo: H264 SWDEC HWDEC VP9 SWDEC HWDEC VP8 SWDEC HWDEC AV1 SWDEC HWDEC HEVC NONE

Troubleshooting already performed

- Installed Microsoft HEVC Video Extensions - Rebooted Windows - Updated NVIDIA drivers - Verified hardware acceleration is enabled - Tested with a brand new Firefox profile - Tested with Firefox Nightly - Confirmed Chrome can play the same HEVC streams

Additional observations

Chrome: - Twitch 1440p becomes available immediately after installing HEVC Video Extensions - Twitch Stats for Nerds reports:

 hev1.1.6.L150.90.0.0.0.0.0

Firefox: - Twitch reports that the browser does not support the required resolution - 1440p remains greyed out - about:support continues to report HEVC NONE

Reproducible tests

Firefox console:

MediaSource.isTypeSupported('video/mp4; codecs="hev1.1.6.L150.90"')

Result: false

MediaSource.isTypeSupported('video/mp4; codecs="hvc1.1.6.L150.90"')

Result: false

navigator.mediaCapabilities.decodingInfo({

 type: "media-source",
 video: {
   contentType: 'video/mp4; codecs="hev1.1.6.L150.90"',
   width: 2560,
   height: 1440,
   bitrate: 8000000,
   framerate: 60
 }

})

Result: {

 supported: false,
 smooth: false,
 powerEfficient: false

}

For comparison:

MediaSource.isTypeSupported('video/mp4; codecs="av01.0.08M.08"')

Result: true

navigator.mediaCapabilities.decodingInfo({

 type: "file",
 video: {
   contentType: 'video/mp4; codecs="av01.0.08M.08"',
   width: 2560,
   height: 1440,
   bitrate: 8000000,
   framerate: 60
 }

})

Result: {

 supported: true,
 smooth: true,
 powerEfficient: true

}

Additional note

Setting:

dom.media.webcodecs.h265.enabled = true

causes HTML5 codec test (https://html5test.co/) to report H.265 support, but does not change:

- about:support - MediaSource.isTypeSupported() - MediaCapabilities.decodingInfo() - Twitch HEVC playback availability

Question

Is this a known issue with HEVC Media Source Extensions support on Windows 11 build 26200, or is there another requirement for Firefox to expose HEVC playback capability through MediaSource and MediaCapabilities when the Windows HEVC codec is installed and functioning in Chromium-based browsers?

i cant get in my you-tube for watch full movies and tell me about DRM and then that Firefox is installing components need to play the audio or video on this page.i need help to fix this

So I clicked into a video, and it did not play. Further troubleshooting showed it was a video hosted by vimeo, and youtube videos still worked. I tried on multiple vimeo hosted videos, on multiple unconnected websites (dropout, patreon, and directly on the vimeo website).

I tried the following fixes:

• I opened it in a private window and nothing played.
• I booted into safe mode, still nothing.
• I turned off all of my add-ons, nope.
• I cleared my cache and restarted, nothing.
• I cleared my browsing data and restarted, also nothing.
• I checked for updates: up to date.
• I created a test profile, and it works there.
• I opened Chrome and it worked there too.

The test profile/chrome thing suggests it's an add-on or something but the fact that I turned them all off and this still happened has me baffled.

Update: I fixed it. Was user error.