Firefox コミュニティフォーラム

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.

Hello. For a while now I have been using the picture-in-picture feature to play a video in the corner while using other applications. It has been a great help as I have a single monitor.

Unfortunately, I have recently been encountering a severe issue with the feature over the last week. When attempting to use picture-in-picture while my computer is running a videogame (through Steam) my entire system will freeze. The audio still plays as normal, but the image is frozen and the system is unresponsive until I force a shutdown and reboot.

Any help at all in with this issue would be greatly appreciated, thank you.

Hardware Specs: GPU AMD Radeon RX 6750 XT CPU AMD Ryzen 5 5600X 6-Core Processor 3.70 GHz RAM 16.0 GB OS Windows 11 Home

I have tried everything. I've gone into the permissions, I have it set that everything is allowed. I reset and forgot the sites multiple times, zoom and Google Meets, and when I reload still the same issue. It says I do not have a camera. The camera works for both Edge and the camera app on my laptop. I even checked my settings on my laptop, and Firefox has permission to access my camera. However, in the camera request history, it does not show that Firefox asked for access to my camera. It also says the last time it accessed my camera was last year, but I have been trying to get it to work this entire time. I am updated with Windows 11 and the latest update of Firefox. How do I fix this? Is it an issue with Firefox or Windows?

Firefox just keeps getting slower and less responsive. I've cleared the history etc and run my Avast cleanup premium which helped a little, but the other browsers just put it to shame. I hate to switch because I love the user interface, but............ its just frustrating. Windows 11 latest updates.

On May 1st, when I launched Firefox(afternoon some time on US East coast) it ran an update to 138.0.1. When it was done, it did not launch. So I clicked the icon on my desktop and it came up, but then closed out after about 15 seconds. When I reopened it, it asked to continue in troubleshooting mode or refresh. I tried both. No luck. I restarted and even uninstall and reinstalled the latest version as well as tried installing 137.

I have tried with virus/malware protection/firewall off. I have restarted. My page file is default. I tried renaming the firefox.exe to something else. I tried creating an new firefox profile(firefox.exe -p) but that crashes too.

I installed the latest version of Firefox Nightly and it stays open just fine. But when I launch the regular firefox, they both close.

I also installed the Firefox app from the Windows store and it behaves the same as the one from the mozilla website.

My Firefox Browser keeps crashing at random times. I was using Chrome previously and it was worse than the Firefox performance. I just installed 128 GB of brand new DDR5 RAM which I tested in windows with no error. I have no malware on my computer currently. I ran all of the usual checks that you suggested with regard to extensions and cache. Here is the most recent report ID that was generated by Firefox:

bp-7c5d5dcf-2fc9-40a3-9659-ff55f0250424

Firefox (current version:137.0.2 64-bit) does not allow drag from outlook on the web and drop on windows 11 file explorer. It shows a forbidden sign when i am dropping on file explorer.

How this problem can be solved?

Since the last update (136.0.4 (64bit)) firefox only partially shows an embedded google spreadsheet. It was fine in the previous version. Tried turning off enhanced tracking protection, but that didn't do anything.

Please provide the exact requirements for defaults in order to have the settings (occurring on the bookmarks settings) to state that Firefox is your default browser. Having had to attempt this process multiple times causes me to question if it is the user that needs some "tender loving care".

Sat. 04/19/2025 @9:10 am CDT - Hi. About 2 months ago on any Settings page, FF began to show "your browser is being managed by your organization." The problem is - it's a STANDALONE box, not connected to any network beyond my ISP. I do own websites but I'm not perpetually logged into the host company, so their switch to Microsoft Entra wouldn't have an effect, I would think.

What settings do I change to make FF know that I'm not on a network? Thanks in advance.

Firefox is no longer compatible with my bank's system. I can't log in with the secure access code the bank sends to verify my identity when using Firefox. The bank says it is a problem with Firefox. Other browsers work flawlessly ... are you working on a solution? I only use Firefox unless forced to use something else ...

My issue is that if I access the upper right corner of the screen, titled "Open Application Menu" and go to Settings I'm told my Browser is not the default AFTER THE PROCESS OF JUST MAKING IT THE DEFAULT.

It seems there is an effort to try and drive all of us nuts. This never happened before, and if it continues it will be the end of electronic communications (which it is suspected is the plan by those who engage in violence to achieve their objectives).

What I came here for was to have my settings, after the process (done many times previously) show a response in Settings that, "Yes" my browser (Firefox) is the default, which it did for a time today. Obviously there is no persistence.

When I got help on this issue previously, my response was I already tried that, and it didn't work. There used to be a lot of different browsers. Now I haven't come across any of them currently. Some are having great success in seeing to it that only their browser will survive. That seems like a "gangland" type of mentality to me.link text I believe I spent enough of my time on this issue and explained it in detail. There's really nothing else I can "contribute".

I, by the way, went to my Internet provider today who found an email under Preferences that she said had the capability to steel my emails. It had an extension in Australia (*.AU). If that has anything to do with this problem I'd like to buy a pair of handcuffs to see if that individual(s) being constrained from using a PC keyboard is a cure for this problem.

I am trying to install firefox on my new work laptop. The OS is Windows 11 Pro. It came with an ARM CPU. Specifically: Snapdragon(R) X Elite - X1E80100 - Qualcomm(R) Oryon(TM) CPU. Everytime I try and install Firefox, which is probably over 10 tries by now, it fails with generic errors. I have tried cleaning everything Firefox related off the PC before subsequent attempts and still get the same errors. I am including a screenshot of what I see shortly after starting the install process.

cannot open allmusic.com website anymore on firefox. this website opens fine on other browsers. Only Firefox is the problem. Any suggestions?

'Running ver 137 and now cannot print to my system default printer. Tried the Troubleshoot fix and same result - defaults to PDF. Is there any entry in about:config to ensure system printer is selected. I have checked all system settings and brother printer is the default.

As I was downloading a video from Google Photos, it showed the yellow by the download arrow and said it failed. I tried multiple file types: mpeg, jpeg, mp4, exe. I googled what to do and my answer was: Disable extensions, start in safe mode, clear cookies, clear history, clear download history. I did all that and I can still not download. I restarted my computer and nothing changed. on FF version 136.0.2

Hello! I started encountering this problem as I updated my OS to windows 11. I had eset nod antivirus, but uninstalling it nothing changed. Tried to change MTU cache size through CMD. Changed different DNSes Tried to disable all protection settings in browser and in windows settings. Deleted all extensions. NOTHING helped except clearing cache of the browser, but this is fixing problem only before first browser restart. Other browser on laptop works normally without any issues.