How to Enable JavaScript in Firefox [STEPS]

Mozilla Firefox is open source free to download and use web browser available on almost all platform. Due to its simple and clean user interface it is been used by millions of user across the world and is very popular amongst older generation due to it being minimalistic. It provide user with track protected mode with ad free experience and add-ons extension tool. It also provides a faster download speed in some cases.

Just like many of the popular and modern web browsers it also supports JavaScript, this means user can have animations and display advertisements from the website. Even though it is enabled by default but it is not in your case then the answer to how to enable JavaScript in Firefox is mentioned below with steps and instructions on how to do so.

How to Activate JavaScript in Firefox on Windows 10

These are the steps required to enable java scripts on your Mozilla Firefox browser in Windows Operating System:

  1. Launch Firefox on your computer system.
  2. From the top of the window, click in Address bar.
  3. Access advanced settings by navigating to following URL.
  4. Type about:config and hit enter key.
  5. A prompt will appear on your screen.
  6. Check the box beside “Warn me when I attempt to access these preference”.
  7. Then, click Accept the Risk and Continue button.
  8. Click the search box below navigation keys in Firefox.
  9. Now type JavaScript and press Enter key.
  10. From list of options, find enabled in preference name section.
  11. If the setting is set to true then JavaScript is already enabled.
  12. And if it set to false then click the undo icon beside the name.
  13. Also you can switch between the settings by clicking the toggle icon.
  14. JavaScript is now enabled on your Firefox browser, close the settings tab to save the setting.

Note – Be very cautious when modifying advanced options because there if you messed up sensitive settings it can cause your web browser to malfunction and sometimes even completely stopped working altogether. Also be wary of the alerts because it save you from potential disasters.  

How to Activate JavaScript in Firefox on macOS

If you have a device with macOS then follow the steps given below to activate JavaScript on Firefox browser:

  1. Open Mozilla Firefox on your device.
  2. Access a new tab in browser.
  3. In the address bar of the new tab, click and type the following.
  4. about:config and press Enter key on your keyboard.
  5. If warning prompt, press Agree to be careful button.
  6. Now click Continue to go to next page of settings.
  7. Find the section named Preference.
  8. Now in JavaScript row, double click.
  9. Refresh Firefox browser and you are now ready to use JavaScript on macOS device.

How to Disable JavaScript on Firefox

If you decide to disable JavaScript settings in your Firefox browser the follow the steps given below:

  1. Open Firefox on your device.
  2. In a new tab, type about:config and press Enter.
  3. Now accept the warning screen prompt.
  4. Click Accept the risk and continue button.
  5. In preference search bar, type JavaScript and press Enter key.
  6. Now beside enabled option, click the toggle icon till the result came as false.
  7. Refresh the browser and save the settings.


JavaScript is a programming language and is required by many new website to function properly as intended therefore it is important to have them enabled on your favorite browser like Mozilla Firefox. If you want to know how to enable JavaScript in Firefox then don’t worry we have listed all the methods with their required instructions and steps in the above article.

adileqbal Author

Leave a Reply