Firefox Community Forum

Hello,

I recently updated my Firefox browser to the latest version, 138.0.1 (64-bit), on Windows.

After the update, I noticed that when playing videos in fullscreen mode (for example, on YouTube or other video websites), the Windows taskbar (the bar at the bottom of the screen with the Start menu icon) does not hide automatically. This is affecting my fullscreen viewing experience.

Before updating to version 138.0.1, the Windows taskbar would hide correctly when entering fullscreen video.

I was wondering if anyone else has encountered a similar issue with the Windows taskbar not hiding, or if there are any suggested solutions to help resolve this problem.

Thank you for your help!

Do you know of a mod that won't allow Youtube to have a resolution higher than 720p, including when embedded? I almost-always have Youtube at 480p when watching through their site. I noticed that when watching a video on another site and that it's embedding Youtube, that the resolution is higher > 480p and in those cases it's not rare to be > 720p.

I'd like a mod or setting so that when it's active that Youtube can't have a resolution higher than 720p, including when embedded. Any idea if there's something alike?

Thank you kindly for your help

This issue just appeared. Video will not play in Firefox. Windows10 PC, up to date with latest versions, as is Firefox. There is no error message or code. Just the spinning wheel. I see other people are having the same issue but I haven't seen a solution. Any ideas or help appreciated.

I've recently done a clean reinstall of Windows 11 and have noticed that, only for Firefox (134.0.2, build ID 20250120135430), a few videos playback without any audio, yet the same videos play with audio when using edge as a comparison. Most (if not all) of these videos did play with audio in Firefox prior to this reinstall.

Firstly, I'm pretty sure this is not a windows sound mixer issue since many videos on the same page and tab play back with audio just fine in Firefox. The same goes for it not relating to the Firefox setting 'Speaker selection', under (burger) > settings > privacy & security > Permissions because videos of different formats (or using different players) on the same page play back audio fine. The tab is not muted. Again, some videos on the same browser tab play audio fine; some of a particular format or player only play the video, while missing the audio (and where Edge plays the same video with audio).

Another common and potentially relevant issue I've seen is that, this being a 'Windows 11 N" install, it was initially missing the settings > system > optional features > Media feature pack, but that is now something I've successfully added. I should add that windows did report problems when I initially tried to add the media feature pack but, after a very long delay, it eventually appeared to succeed when I ran a couple of DISM incantations that I think ended with - "dism /online /add-capability /capabilityname:Media.MediaFeaturePack~~~~0.0.1.0"

I have the 'Play DRM-controlled content' setting enabled.

Comparing the Firefox vs Edge video playback on this video test page - https://tools.woolyss.com/html5-audio-video-tester/ I get the following results (don't know how to get it formatted/aligned correctly, sorry) -

                           FF vid    FF audio    Edge vid    Edge audio
av1-opus-sita.webm          Works     Works       Works       Works
vp9-vorbis-spring.webm      Works     Works       Works       Works
vp8-vorbis-sintel.webm      Works     Works       Works       Works
avc-aac-nerdist-friends.mp4 Works     MISSING     Works       Works
avc-aac-big-buck-bunny.m4v  Works     MISSING     Works       Works
avc-mp3-sita.mov            Works     Works       Works       Works

And perhaps also relevant is that there's also a difference in the audio-only samples further down the table on the same page -

                   FF audio   Edge audio
audio-sample.mp3    Works      Works
audio-sample.weba   Works      Works
audio-sample.ogg    Works      Works
audio-sample.opus   Works      Works
audio-sample.flac   Works      Works
audio-sample.wav    Works      Works
audio-sample.m4a    FAILS      Works
ac192.mp3           Works      Works
spoonradio-hd.aac   FAILS      Works
audio.opus          Works      Works

Also, every 'v.redd.it' / reddit-video-player video plays the video fine but has no sound when using Firefox but plays both sound and video fine with Edge. Here's one for example - https://old.reddit.com/r/funny/comments/1i7y1nr/rock_paper_scissors/

I've seen lots of similar (but not identical) issues on Firefox video with no audio problems with suggestions a few things to try. In addition to what I've already mentioned above, I've tried the following without success -

- Restarting Windows - Restarting Firefox - Restarting Firefox with addons/extensions disabled - 'about:support' > Refresh Firefox - 'about:support' > Clear startup cache - (hamburger) > more tools > task manager > (click the little profile icon for the page playing the video) - I've checked the settings suggested here: https://support.mozilla.org/en-US/kb/fix-common-audio-and-video-issues#w_check-some-firefox-settings

I realise it may be possible to side-step this problem by flailing around with more drastic work-arounds like trying a clean re-install of Windows or a full uninstall and clean of Firefox, but that doesn't really help figure out the problem, which leaves the possibility it could easily happen again to me or others when it might be something that can be more properly fixed or guarded against in Firefox itself, so I hope someone can suggest what might be done to home in on identifying the cause of the problem and so learn whether a more precise fix can be employed.

Maybe after update, or i dont know why, but now. when youtube (or any other videoplayer) in fullscreen - taskbar menu is visible (Is on topscreen). In google chrome problem is not repeats. I'm using StartAllBack app for classic start menu, but till that day all was fine. I checked on two devices with firefox - the same problem (StartAllBack or windows version wasnt cahnged). Windows 11 24H2

Initially connects video playing to Headphones via Bluetooth then audio stops. Reloading doesn't help. But the same works perfectly on other browsers. Problem is with Firefox audio setting. The problem started only a week ago for firefox

Recently decided to try Mozilla for Windows. There is such a problem, and only on Mozilla: the video is very overexposed, the brightness is high, like in a fog, and on all video services, including YouTube. At the same time, I checked on all the other 3 browsers - everything is fine with the video. I did not change any settings in Mozilla, everything is by default. How to fix it?

I've been searching for an answer to this for weeks to no avail. It concerns YouTube videos "autoplay"ing on YouTube. Many have asked this question and most responses state to shut off Autoplay. These are two separate issues. AotuPlay means the next video on YouTube will advnace automatically requiring no user input. If Autoplay is off, streaming stops at the end of the video. The issue I am having is when I open a YouTube video to a new tab (but do not switch to that tab), the video WILL start playing as soon as that tab is in focus. This never used to happen and indeed, on two other computers with the settings and extensions all sync'ed, this doesn't happen, except for on this one computer. Today I found someone that posted the exact same problem 5 years ago and didn't get an answer. He seems to describe it well:

1. Okay, so before, when I loaded up 100+ Youtube videos, they stayed when switching tabs - no autoplay. Suddenly they decide to autoplay when switching tabs - note, I've not done anything to my settings or plugins. Fair enough, maybe you changed something (which you often do, without informing). So I check the options. It was on "Block audio", which obviously didn't work, so I tried "Block Audio and Video" - which WORKS, but now both the video is paused (which I want) AND the audio is set to mute (which I DON'T want) - so... what does it take to have Youtube wait for a click to start playing a video loaded in a background tab, but KEEP AUDIO ACTIVE, so I don't also have to unmute the damn video?

One person posted a possible solution: Maybe check this pref on the about:config page.

   media.block-autoplay-until-in-foreground 

This setting describes the issue kind of. If you have this set to false, the moment you send a link to a new tab, YouTube starts playing in the background. Setting it to false keeps the video paused until that tab is in focus. That is how mine has always been set. What I am looking for is a setting that would say something like: "block autoplay until play is pressed"

Thanks in advance and sorry for being so long-winded

Can't seem to stream Netflix. Firefox is up to date. New Widevinecdm update today 4/2/2025. Apparently since that update (today) I can't stream. I get Netflix error code F7702-1003. Searched/read several FF articles/forum Qs - no help. did a "refresh FF" - no help. don't want to install Chrome (Google knows too much about me already). Netflix worked fine last night. Tried unchecking "play DRM controlled content" - FF(Netflix site) asked to enable DRM - clicked ok - reinstalled. no help. Hard reboot - no help. Still running a Win7 64-bit desktop OS - works fine.

HELP!! Thanks

Yesterday I updated Firefox to version 115.22.0esr this morning when it was released. Have never had any problems viewing video on Netflix but now I am getting Netflix error message F7702-1003. Yesterday I asked "what can I do? I've rebooted computer as Netflix says and it didn't help."

Today, to see if the issue was a bug with version 115.22.0 esr I logged onto both Peacock and Hoopla to try to stream video. On both sites the same thing happened that happened on Netflix. I log into the site, select a video, and when I try to play it I get a message that "widevineCdm plugin has crashed" and video won't play.

Since this problem just appeared after I updated to version 115.22.0 esr it seems likely that there is a bug in this version which is crashing the plugin and preventing streaming video. I note that I can stream some video having checked both YouTube and an online television station.

Can you guys check why your netflix account is getting logged out every time regardless of how many times you logged in and for prime video if you play any video i'm getting video player error, can you please check

Since the latest update to my Firefox, videos (for example, in documents such as surveys) either do not load or they freeze. And in some streaming applications, either they play with no sound or when sound is turned on the video freezes. This was never a problem until recently. iMac desktop (2017) Ventura 13.7.4 Firefox 136.0.2 (64 bit) The same issue does not occur on Safari or on my iPad (using Firefox). Any advice?? Thanks.

Windows 11 Pro - Dell XPS8940 desktop - i9

Firefox will not play video from a website. If I save the video, it is a MP4 file. Windows Media Player and VLC will play the video file. But the browser shows the message: "No video with supported format and MIME type found."

Chrome and Edge will play this video correctly in their browsers. Firefox will not play the video on 3 different computers, and even when a different user account is involved (without Firefox sync).

The evidence seems to point at firefox. The website is a Wordpress site.

Is it possible that the website is the problem? If so, why do Edge and Chrome work?

I uninstalled Firefox (latest version) and reinstalled it. Not fixed.

My windows updates are current, as are Dell updates.

This is stumping me. I hope someone can help.

This is the link. I can't send animated images as the text is too small, so I'll describe it instead. It's so hard as a loyal fan, I'm crying.https://www.bilibili.com/bold text。There is a bug. Why does the Bilibili website not display the corresponding screen when I try to move to it? Speed playback cannot be used at all, and there’s also the issue of not being able to use fullscreen on Firefox. Are you forcing me to use another browser?

I have a Microsoft Surface Pro 8 with a Slim Pen 2. I do a lot of searching in google maps and have noticed that I can access google maps and can use pinch to decrease and expand the maps and if I open a street view I can use touch to move the field view around as it should be. The problem occurs is when I use my slim pen. Once I have used the slim pen to move a field or open a street view the touch capability stops working. I can still close the window and other things with the touch capability (system type functions), but within the browser it's disabled.

I have not noticed this occurring in any other web site or type. For example I can go to amazon and interchangeably use the pen and touch capability without issue.

I have tested this in Google Chrome and MS Edge and it does not disable the touch capability when I use the pen.