MIME type not found (MP4)

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 … (xem thêm)

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.

Được hỏi bởi Michael 7 giờ trước

Lần cuối trả lời bởi jonzn4SUSE 4 giờ trước

Animation-Timeline CSS property not working on Firefox

I used the CSS animation property called animation-timeline , which is written as: element{ animation-time: view(); } When I view the webpage on Chrome, Edge, Opera, a… (xem thêm)

I used the CSS animation property called animation-timeline , which is written as:

element{ animation-time: view(); }

When I view the webpage on Chrome, Edge, Opera, and even on Phoenix browser, the animation works.

It is only on Firefox that the animation does not work. I even added the Vendor-prefix of " -moz-animation-timeline " to the CSS property, and it still didn't work on Firefox, while it is working on all other browsers.

The CAN I USE website ( https://caniuse.com/?search=animation-timeline ) tells me that Firefox does not support it at all.

It however said that I can enable it, by setting "layout.css.scroll-driven-animations.enabled" to true.

1.) I don't know what that means.

2.) Would my website's users be able to see the animation on their Firefox browser, if we assume that I make this setting ?

3.) I am using Firefox version 138.0.3 (64-bit) : What can I do to see that both I and users of my website are able to see this animation on Firefox ?

Regards.

Được hỏi bởi Gamicord 1 ngày trước

Lần cuối trả lời bởi Mark 4 giờ trước

Firefox is syncing to bookmarks i had 5 years ago rather than most recent

So I had to reset my pc, and i didnt think to export my password and bookmarks since I'm logged in and sync is on. Now its only syncing to what I had 5 years ago rather t… (xem thêm)

So I had to reset my pc, and i didnt think to export my password and bookmarks since I'm logged in and sync is on. Now its only syncing to what I had 5 years ago rather than just earlier today. Can't seem to figure out how to fix it.

Được hỏi bởi amanift 4 giờ trước

arrow keys and allow a website to open a window

Changed behavior of autofill is a small thing. A few weeks ago, I could enter the first few letters of a site and then down arrow to choose one from the list. Down arrow … (xem thêm)

Changed behavior of autofill is a small thing. A few weeks ago, I could enter the first few letters of a site and then down arrow to choose one from the list. Down arrow no longer works here.

A significantly bigger issue allowing a website to open a window or tab or popup. There used to be two buttons when this happens, allow and always allow. Always allow is no longer a choice. I have to click allow every single time I go to that web site. Since two of those sites are the enrollment and learning management systems where I work, I'm doing that 20 times a day. If disappearing the always allow button was a design decision, it was a bad one.

Được hỏi bởi pjcamp 6 giờ trước

Lần cuối trả lời bởi Mark 5 giờ trước

Firefox on Linux (Manjaro Gnome) becomes unclickable

In the last few days, after some minutes of usage, parts of Firefox become unclickable: - I can still click on tabs to change tabs. - When hovering over the cross button… (xem thêm)

In the last few days, after some minutes of usage, parts of Firefox become unclickable:

- I can still click on tabs to change tabs. - When hovering over the cross button to close a tab, it changes appearance as it should. Clicking the button does nothing. Ctrl+w still closes the button. - Clicking on the address bar does nothing. - Cannot click on back, forward, refresh buttons. - Cannot click on any add-ons. - Cannot click on preferences. - Can click on the button to open a new tab. There, I can enter an address. Once the page has loaded, address bar becomes unclickable again. - Bookmarks toolbar is still working as expected. - Keyboard shortcuts (ctrl+t, ctrl-w, ctrl-l) still work as expected.

I'm running ``` Mozilla Firefox 138.0 20250428130755 20250428130755 ```

on Manjaro 25.0.1 with GNOME 48

Được hỏi bởi mladen.ivkovic 1 tuần trước

Lần cuối trả lời bởi mladen.ivkovic 6 giờ trước

. "Firefox had a problem and crashed. Unfortunately, the crash reporter is unable to submit a report for this crash." Inside a box there is the comment "Expected value at line 1 column 1." Firefox will not start up. For some reason, it will not copy.

Tell me how to fix this. I don't go into registries etc.. So, if the fix is at that level, please tell me what it is on a form that I can copy from and give it to whateve… (xem thêm)

Tell me how to fix this. I don't go into registries etc.. So, if the fix is at that level, please tell me what it is on a form that I can copy from and give it to whatever tech I can find to hire to fix the problem. Love to add images, but your notice of the crash is set up to make it impossible to copy.

Được hỏi bởi TERRY FITZGERALD 6 giờ trước

How do I actually use my custom made theme?

I made a custom theme for firefox and submitted it to AMO. It's approved, but I have no idea how to actually apply it. I don't see any option to install or use. What am I… (xem thêm)

I made a custom theme for firefox and submitted it to AMO. It's approved, but I have no idea how to actually apply it. I don't see any option to install or use. What am I missing? How do I actually use it?

Được hỏi bởi nicoleashleyjay97 14 giờ trước

Lần cuối trả lời bởi Paul 6 giờ trước

Unable to set up duckduckgo as a search engine

I added the duckduckgo extension and gave it the required permissions, but despite it saying that it set duckduckgo as the default search engine, it hadn't even showed up… (xem thêm)

I added the duckduckgo extension and gave it the required permissions, but despite it saying that it set duckduckgo as the default search engine, it hadn't even showed up on the list at all. I tried removing and adding back the extension, but that didn't work either.

Được hỏi bởi Erin Haliat 1 tuần trước

Lần cuối trả lời bởi Mark 7 giờ trước