Skip to content

How to Fix: Firefox Not Playing Online Videos

Firefox is not playing videos caused due to some minor problems or settings of your browser. You can quickly fix this problem by using various fixes such as updating the Firefox, Refreshing the browser, disabling the extensions, clearing the cache files, etc. One can use all these fixes to resolve their problem quickly.

Mozilla Firefox is one of the fastest browsers with many features, privacy protection, and customization options. The popularity of Firefox has declined since Google Chrome was released, and both browsers are giving each other tough competition.

Firefox still has a very loyal fan base. If you are also a fan of Firefox, you might face difficulties playing videos on Firefox. There are many factors due to which this can happen.

Recently my younger sister kept facing the same problem with Firefox. She was trying to watch some videos on a website and kept receiving an unknown error has occurred on the screen. She then asked me if I knew how to fix this issue. I researched online and suggested some troubleshooting steps to solve her problem.

Before starting, you must try two short and quick fixes to resolve Firefox not playing videos. The first one is that you should try restarting Firefox. And the second one is that you should check your internet connection by running a speed test.

If any of these fixes help, you do not need to move ahead since it was a temporary issue. But if these fixes do not help, continue with suggestions for troubleshooting.

Update Firefox Browser

One of the best ways to fix Firefox not playing videos is to update the Firefox browser. There might be a chance of having the older version of Firefox, which the video player doesn’t support. Hence the latest version might include the support.

Here are the steps to update Mozilla Firefox to the latest version:

  1. Launch the Firefox browser on the computer.
  2. Click on the More horizontal 3bar icon for options menu.Firefox Browser Options Menu
  3. Select the Help > About Firefox option.
    About Firefox Help Section
    The About Mozilla Firefox window will appear, and start checking for updates.
  4. Firefox will download the updates and automatically install them in the background.
Firefox Quantum is up to date

I may also ask to relaunch the browser for significant upgrades. After updating, you will not lose your data or the passwords saved in Firefox. Instead, you might also enjoy the new features that have been recently added to Firefox.

Clear Cookies and Cache

Sometimes data collected in cookies and cache could prevent videos from being played. Clear cookies, history, passwords, and browsing data to free up space for new videos to load and play.

Here are the steps to clear cookies and cache from the Firefox browser:

  1. Launch the Firefox browser on the computer.
  2. Click on the More horizontal 3bar icon for options menu and select the Options menu.
    How to block sound acess in Firefox computer
  3. Switch to Privacy & Security tab in the sidebar.
  4. Scroll down to the Cookies and site data section.
  5. Click on the

Clearing the Cache will free up some space in Firefox that might help load the videos and play them. But this will also log out the sign-in you might have in Firefox.

Disable Add-ons and Extensions

An add-on or extension could be why the video plays in private mode and not in normal mode. Try disabling all extensions and plug-ins one by one and check if the video plays.

Here are the steps to disable the Firefox Add-ons or extensions:

  1. Launch the Firefox browser on the computer.
  2. Click on the More horizontal 3bar icon for options menu.
  3. Select the Add-ons and Theme options from the list.
    Add-ons and Themes option in Firefox Computer browser
  4. Switch to the Extensions from the left sidebar.
  5. Toggle the Disable option of every extension.
    Toggle Button to disable the Firefox Add-on

You can either disable all the extensions or enable them one by one to check which is causing the problem. You can also disable them one by one and check simultaneously; anything per your preference should work.

Enable Autoplay on Firefox

Firefox blocks videos with sound from playing automatically by default. You will need to enable the auto-player to play online videos in Firefox. It would be best to consider this a troubleshooting step; auto-playing the video is annoying.

Here are the steps to enable Autoplay in Firefox Computer:

  1. Launch the Firefox browser on the computer.
  2. Click on the More horizontal 3bar icon for options menu.
  3. Choose the Options tab from the list.How to block sound acess in Firefox computer
  4. Switch to Privacy & Security tab and scroll down to the Permissions section.
  5. Click on the Settings… available next to the Autoplay. 
    How to allow sound access in firefox computer
  6. From the default for all websites dropdown, choose to Allow Audio and Video.
  7. Click on the Save Changes command button.
    How to allow sound access in Firefox computer

When you enable autoplay in Firefox, the videos that appear in Firefox will be played automatically without any actions or clicks. It might consume a bit more data, but you should consider checking the JavaScript setting if the video starts to autoplay.

Reset Firefox browser

If anything mentioned above fails to solve the issue, you can completely refresh Firefox. It could be required as some programs or extensions might have changed some settings, and you cannot fix it.

Here are the steps to reset and refresh the Firefox browser:

  1. Launch the Firefox browser on the computer.
  2. Click on the More horizontal 3bar icon for options menu, and select the Help menu.
    Firefox Help option menu
    It will expand the Help menu.
  3. Click on More troubleshooting information from the sub-menu.Mozilla Firefox More Troubleshooting Information menu under Firefox Help
  4. Select on the Refresh Firefox… button.
    Refresh Firefox button to reset browser
  5. Hit on the Refresh Firefox in the confirmation dialog box.
    Refresh Firefox to Remove Customization and Settings

The refresh or reset will remove all the customization and settings to make Firefox as fresh as new; however, the saved data, like bookmarks and passwords, will stay intact.

Bottom Line: Firefox Not Playing Video

You can try one by one fixes and stop wherever your problem of Firefox not playing videos is solved. This way, you will also find out the actual bug preventing the videos from playing in Firefox.

The fixes show you could fix Firefox not playing videos. However, it might be frustrating sometimes not to play videos on Firefox. But if you follow the above methods, one of them will surely help you fix the issue in Firefox.

In my sister’s case, the Firefox add-on blocked the website element from loading the video. I disabled the content blocker add-on in Firefox and reloaded the web page to see if the video was working, and it worked.

We hope that you have fixed Firefox not playing online videos. But still, if you have any difficulties streaming videos, let us know the errors and troubleshooting steps you’ve taken.

F.A.Q: Firefox Not Playing Online Video

We have listed some of the frequently asked questions related to the Mozilla Firefox browser not playing online videos:

Why is Firefox not playing videos?

Sometimes highly cached files, old browser versions, or a few specific content-blocking extensions can stop Firefox from playing videos.

How can I fix, Firefox not playing the videos?

Try clearing the cache files and updating Firefox. If this does not fix your problem, try disabling the extensions and enabling autoplay. If that still doesn’t work, then reset Firefox.

Can I fix my Firefox video not playing problem by updating the Firefox browser?

Yes, if the problem is caused due to the older version of Firefox, this can be the solution. But this won’t be the ultimate solution in all cases.

Lastly, if you've any thoughts on How to Fix: Firefox Not Playing Online Videos, then feel free to drop in below comment box.

Disclosure: This page may contain affiliate links, which means we may receive compensation for your purchases using our links; of course at no extra cost to you (indeed, you may get special discounts).

Shubham Kumar

Shubham is a graduate of Information Technology who likes to write about Windows troubleshooting and browser tips. He's always engaged with new tech and gadgets exploring new technologies. He loves troubleshooting tech problems, and writing is the view. Connect with him on LinkedIn.

Share us your thoughts

Your email address will not be published. Required fields are marked *