Firefox Community Forum

I am trying to add an mp4 video to my website using the following code:

<video width="320" height="240" controls>
  <source src="images/###.mp4" type="video/mp4">
</video>

where ### is the name of the video file. I get the following error message:

"No video with supported format or MIME type found."

In the console the following is displayed:

"Media resource http://127.0.0.1:5502/images/###.mp4 could not be decoded. video.html All candidate resources failed to load. Media load paused. video.html Media resource http://127.0.0.1:5502/images/###.mp4 could not be decoded, error: Error Code: NS_ERROR_DOM_MEDIA_METADATA_ERR (0x806e0006)"

Runs just fine in Chrome and I have no pop-up blockers installed. Autoplay is set to be allowed for all websites.

Windows 11 version 23H2. Firefox version: 126.0 (64-bit)

I have used Firefox for Windows for many years and have had no problems until recently. I have been unable to print my emails: when I click on the printer icon in the upper right corner of an email nothing happens. I was wondering if there was something in the settings that was causing this problem. Thank you!

I am experiencing no window to enter my credit card number in. There is the window for the expiry date and CCC code. Just not the card number. I have tried numerous websites that I would never buy anything from just to test the failure and it repeats on all the sites I have tried including government payment site.

So I have an issue where I am unable to reorder or detach tabs after having detached one tab. When I start Firefox I am able to reorder my tabs as much as I want, but once I detach one tab both functionalities do not work anymore.

- Firefox version 126.0 on Kubuntu 24.04 - After restarting Firefox I am able to do it again once - After rebooting I am also able to do it again once - The same issue in private window - I have refreshed Firefox through Help -> More troubleshooting information - Disabled all my add-ons - Tried it in Troubleshoot mode

I cannot seem to find a real answer online. Does somebody here have a solution for me :-)?

Hi,

If I have an unloaded tab on right of the current tab and I close the current one, instead of going to the right tab, which is the unloaded one, it jumps to another tab which I'm not sure has what relation to it, it certainly is not the tab that opened it.

I removed every modified entry of "Browser.tab" in About:Config, installed "Select After Closing Tab", no result.

Thanks

As title- Cannot download for example webm format, but jpg is okay. cannot install any addon, theme or anything. DRM didnt install as well. i was trying reinstall, refreshing browser, rebooting.

If you close a tab that is next to one or more unloaded tabs, firefox jumps those and opens the next one that is loaded. Is there a way to disable this so upon closing it would open the right tab, whether loaded or not. I tried "Select After Closing" add-on, didn't fix it. Disabled Auto Unloading via about:config, same result.

Hi, I've recently downloaded firefox and trying to add extensions that were similar to the ones I used on chrome. My problem is that all the extensions (Hoverzoom, Short Keys) in the extensions tab in the toolbar and appear to not be working (both in private and normal browsing). However the extensions (Ublock, SponsorBlock) that have their own icon on the toolbar seem to be working fine.

I've attached a reference image,

Any help would be greatly appreciated.

When I do right mouse click on page, depending on the mouse cursor position, context menu appears and I need to scroll up or down to access appropriate item. I thought I need to try and fix size and position of a page context menu. Is it possible? I believe it may depend on the screen size and resolution and how many entries add-ons add to right click menu. Examples: https://imgur.com/nocb5kK.png https://i.imgur.com/yNeNJQh.png

On Edge or other search engines I've been able to highlight, copy and past a web address where the pasted result is a clickable link to the website, but this doesn't work for Firefox. I have looked through the settings and other questions online, but found no solution, from what I can see people more often ask about the opposite issue to mine. Is this a limitation of the search engine or am I dumb?

I'm trying to import a password csv file generated by Roboform into firefox password editor. I've exported the csv file from Roboform but when I try to import to the Firefox password page I get: "Incorrect or missing column headers. Make sure the file includes columns for username, password and URL". The csv file does have column headings. Is there a way to do this?

My website is shown as insecure. If I open it with Chrome, it is okay. If my girlfriend opens it from her computer with firefox, it is okay too. What is wrong here?

I am using latest of Firefox and DuckDuckGo. When I type something in the main search bar (in the middle of screen) the text moves to the search field in the toolbar area. I find this annoying. I want to text to remain in the main search bar (middle of screen). Any solution?

Regards Francesco Cembrola

Hello! My name is Anya. I am desperately trying to manage my social media addiction and to help support that I am wondering if its possible to disable the privacy window. I know I can install a website blocker - which I have, but it does not apply to the private window so I have full access to social media on it, I just have to log in. I want to COMPLETELY block Facebook and Instagram off of my laptop. Is this possible? Thank you!

Bonjour, Hello,

I contact you because, even without an adblocker, Youtube is very slow with Firefox navigator. I don't understand why and I don't have this problem with Google Chrome ? Fews years earlier, I never had this problem with slow Youtube when using Firefox Navigator. I don't know if the problem comes from Youtube or Mozilla and I contacted both of them.

Thank you.

Bonjour,

Je vous contacte car, même sans bloqueur de publicité, Youtube est très lent avec le navigateur Firefox. Je ne comprends pas pourquoi et je n'ai pas ce problème avec Google Chrome ? Quelques années plus tôt, je n'avais jamais eu ce problème de lenteur avec Youtube lorsque j'utilisais Firefox Navigator. Je ne sais pas si le problème vient de Youtube ou de Mozilla et je les ai contactés tous les deux.