Firefox supportforum

Some HTML5 videos won't play in my Firefox browser.

This vine for example (https://vine.co/v/b3v5h3Piwt7) only shows up as a static image. I can click the mute/audio button though, but it won't play. When I look at the webconsole when I load the page then 2 javascript warnings show up, the first one say that the Mediasource [long url here] can't be encoded and another one says loading of all candidate sources failed. loading media paused.

I'm using Firefox 21.0 and I tried to run Firefox in safe mode with disabled add-ons, and I also tried to reinstall it, but without success.

Thanks in advance.

I am running Windows 7 64 bit and Firefox is my browser. All of a sudden I can not play videos at places like Democracy Now and many other web sites (E.G. Malcolm Gladwell) but most of Youtube is okay - except sometimes. I thought this may have been due adGuard but disengaging it or starting FF clean with no ad ons has no effect.

I was just informed by Costco Concierge Services that the reason is that both FireFox and Google Chrome have decided to “no longer support” certain add ons or plug ins (what is the difference if any between these tech terms of art?) and therefore if I can not play a video I will have to use Internet Explorer. Discovering what videos I can or can not use is a hit an miss case by case basis.

So, first is this true? I can not imagine Firefox or Google Chrome making a change that would actually require its users of many years to bump their prime product and, instead, turn to its prime competitors. That seems like suicidal sabotage. We are just every day end-users and not software engineers and the explanations I find are absolutely incomprehensible technobabble.

In plain English what is the real problem? What is the fix? And has Firefox actually decided to make us dump Firefox and turn to its competitor just to watch certain videos? Has Democracy Now decided to continue using a video format that is no longer supported by FF?

The attached pic is just and example. DN uses jW player but I find this problem at other web sites too.

About a month and a half ago MP4 videos in Twitter 29 played fine. Then I updated to the latest version of Adobe Flash player on both my Win 8.1 and old XP computers. That is when I started getting "This browser does not support video playback" error when trying to play a mp4 video in Twitter. I ran Firefox in Safemode ... no change. I removed all addons ... no change. All Plugins are Ask to Activate or Always Activated. I uninstalled Firefox and Flash player and reinstalled .. no change. The videos work fine in MS IE II and Chrome 53.0.2785.116 m. H264 Codec is installed. YouTube videos play fine.

Cannot open yahoo or sky inboxes or compose in them when I access them through Firefox.

Also have error message on Firefox that an attempt to change my settings has been blocked. Cannot delete it.

Every web page with video / audio content begins to autoplay (at the vid's highest volume) approximately 5 seconds after opening the page. I could disable this in Safari and Chromium, but see no option to disable the 'Autoplay' feature in Firefox. Worse, there are no plug-ins or extensions available that will allow this to be done. If you have had success disabling this annoying 'feature' (it's not a 'bug,' right?), please advise how it was done so that I may rid myself of these annoying vids. Thanks in advance.

When I've been playing YouTube videos lately, I've noticed that a bunch of black boxes have been appearing over the player interface (The controls below the video) while the video is playing. Unfortunately, I can't provide a good screenshot, as the boxes come and go too quickly for me to get them. This issue still occurs if I restart Firefox in safe mode. I think it started happening with Firefox 37.

Since ± half october 2018 I can't play videos anymore on some sites and get this crash message. Youtube does work, probably because without Widevine? I'm on FF Dev Edition, Mac with El Capitan. Thanks, Pieter

Ever since some update, Firefox won't load Vines or Tumblr videos, but load YouTube videos, Facebook videos, and pretty much everything else. I've disabled hardware acceleration, addons, and tried most (if not every) solution given here.

Hello. So, as the question says, Firefox doesn't drop GPU usage and GPU core frequency (but it drops GPU memory frequency). I tried the other browsers (Chrome, Opera, Edge) and it's fine. I have AMD RX560 graphic card with the latest drivers and I also tried previous versions

Firefox will no longer stream a TV show or keep up even with a 100m internet connection. I messed with it's settings for many hours and asked the community but no response so I tried out Edge which is Unbelievably Fast and can open multiple tabs and stream each show on each tab to completion and even watch them with no internet just like firefox used to be. I was loyal firefox user for many years but no more.

This may sound like word games, but I'm not trying to be funny, merely specific.

So I'm on a network with limited bandwidth. Therefore it's critical for me to understand what settings I can configure (if any) that will prevent the DOWNLOAD of video and/or large images from web sites.

For example, your basic site nowadays probably uses HTML5 and may use that vs. the old-style Flash plug-ins to embed video. And yep classic HTML links with references to image files for the images.

Back in the day you could configure a browser to ignore these references and then the browser would not even attempt to fetch the referenced image or video files. I've recently started using Firefox again, and I'm trying to learn how Firefox handles this in the HTML5 era (or rather what dumb users like me are supposed to do nowadays).

I'm noticing most of the help literature is regarding disabling settings of the auto-PLAY feature. However, due to my ignorance of modern Firefox, perhaps I'm reading it wrong, but most of it seems to involve disabling plug-ins that activate after the file is downloaded, not preventing the actual download. Similar to if I'm using Microsoft Word to view a DOCX file from a web site, uninstalling Word doesn't prevent the DOCX file from downloading. What I don't want to do is cheerfully disable the video playing while my browser still happily downloads the video in the background... because my main goal is not to avoid the annoyance of autoplay, but my goal is to conserve bandwidth on my connection.

FYI I'm using the latest version of Firefox Quantum on Manjaro Linux.

Thanks for advice anyone can provide in helping bring me into the "now" of modern Firefox, or who can point me to any further help articles or instructions to help educate me about this. If I'm over-reading and disabling auto-PLAY also inherently disables the downloading of the associated media, super, but that distinction is not obvious in any of the documentation I've seen so far.

Thanks!!

Alright, so first the story, then the specifics.

Story: I updated to Firefox 55.0 a few weeks ago, presumably when it came out, as I had auto-updates enabled. Immediately after doing so, the large majority of videos would crash my tab. I'd get what I can only assume is the standard message of "Gah, My tab crashed!" etc. Anyways, I did some digging around, these forums and others, none of the solutions worked. I settled for the quick n dirty solution, and rolled back to firefox 54.0, which worked fine. Until today. Today, 54.0 was experiencing the issue as well, so I naturally decided to try 55.0 - which didn't work either. That leaves me where I'm at now.

Specific details: Tabs crash upon trying to load a video, presumably of a different format. It crashes occasionally on youtube videos, but is for the most part OK with them. Scrolling through a facebook feed however, will give you videos from lots of different sources, and I can reliably crash my tab within 10s if I load up facebook and just scroll down.

Potential fixes I have tried (of which, none solved my issue):

• Going into About:config and changing the browser.tabs.autorestart and browser.tabs.autorestart2 both to be false. This is following the recommendation of another thread, given to a different user with a similar problem, found here: ( https://support.mozilla.org/en-US/questions/1159697 ).
• Booting the browser up into safe mode
• Updating any/all drivers. Specifically I can for sure, without a doubt, say that my gfx card drivers are up to date.
• Creating a new firefox profile, and using it instead.

At this point the only thing that comes to mind is the idea that the plugin loading these videos isn't working correctly? But is it even a plugin?

Worth noting, if I change the about:config file pieces I listed above to both be false, instead of crashing a tab it will crash the entire browser. A crash report of that specific incident can be found using bp-92e3bbb7-9388-4412-9573-504010170905 .

The normal issue happening can be found using bp-a8e33356-c344-4159-889b-b330a0170905 .

Thank you for any/all help you can provide.

I have a MacBook Pro (Retina, 13-inch, Early 2015) with firefox as my browser. I"m having a problem with playing videos and have tried to use firefox help lists to no avail. If I force quit the browser and then reload it I can play about 5-6 videos but after that it just buffers and tells me to restart my computer. I have removed adobe flash player and reinstalled it. I have removed the ad blocker I had on the computer and didn't re-install it. I have tried other things that are on the internet, nothing works. Any suggestions... please

I've recently built a desktop PC with this configuration:

Ryzen 7 1800X

Geforce GTX 750 Ti (driver version: 399.07)

16GB DDR4 RAM

250GB SSD + a HDD for data only, no system files

Windows 10 64bit

External Sound card Scarlett 2i4 1st gen. [it worked fine with my old Windows7 desktop]

Any audio (soundcloud, zophar.net/music) or video (youtube, twitch, facebook) stream has the same problem: it randomly skips frames. I mean that video nor audio are interrupted, they continue, but they skip some "frames".

This bug occurs with the current official version, the current beta version and the current Nightly.

This bug does not occur on my laptop, windows 8 running an i5 CPU and no dedicated GPU.

This bug does not occur on other apps. I've tried: VLC, Facebook app, Twitch app, Microsoft Edge, Internet Explorer, Winamp.

I updated to Firefox 35 recently and now HTML5 videos will not work. I do have NoScript, but disabling or removing it does not fix the problem. Switching to safe mode does not fix the problem. The problem is solved by using a fresh profile or deleting the prefs.js file, but this is not an option for me, as restoring all my settings from scratch would be a time-consuming hassle I'd rather not deal with.

I know the problem is with the update to Firefox 35 specifically because everything was working fine before and stopped working after. To be absolutely certain, I turned on my laptop that had the same exact extensions and settings imported to it from this computer with FEBE a while back. It was using version 34.0.5 and everything was fine with that version. I tested it with the Vine website, all videos worked. It also downloaded the update to Firefox 35 in the background and as soon as I restarted it, the HTML5 videos were broken.

It's definitely something Mozilla changed but forgot to alter/remove an old setting that's gumming up the works. If I could just figure out which line(s) in the prefs.js file was causing the issue, I would delete/modify it myself in Notepad.

For the record, I already had media.windows-media-foundation.enabled set to false. All videos that use Flash seem to work. I think Vimeo uses HTML5, but it's the only non-Flash video site I could find that still works. Flash and Java have been updated to the latest versions.

an invisible screen. Sometimes, I can remove it using Inspect Element. For example, on YouTube, the block is coded;

<div id="theater-background" class="player-height"></div>

After I remove the above, the block is gone. How can I get this to not be there in the first place?

I have developed a very basic opening page for my web site. It contains a 45 second movie. It works on IE, Chrome, and Safari but will not work on Firefox. Why?

I have spent numerous hours attempting to try workarounds with no luck. I am considering just putting a statement on my front page that says I cannot make this site work properly with Firefox.

It would seem to be in Firefox's best interest to figure this out and fix it vs being the lone browser out there where basic common video formats do not work well.

Please let me know if there is a very quick workaround to make this work because I am certainly not going to spend any more time trying to figure it out.

Thanks for listening

I am unable to watch videos in Firefox since the last update. There is a spinning wheel and it never finishes loading. Since I reinstalled FF, there are no external plugings. Tried re-install, restart, nothing worked. They do play properly in Chrome.

Client said that video cannot load on firefox except other browsers. It shows "Video format or MIME type is not supported". Firefox version is 33.0.3. Video is mp4 format.