How to Disable JavaScript in Firefox

Firefox Start Page

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On occasion, it might be necessary to disable JavaScript for development or security purposes, or maybe you need to turn off JavaScript for performance reasons or as part of a troubleshooting guide.

Regardless of why you're disabling JavaScript, this step-by-step tutorial explains how it's done in Mozilla's Firefox browser. Disabling JavaScript should only take a couple minutes, even if you're unfamiliar with how to use Firefox's settings.

How to Disable JavaScript in Firefox

  1. Open Firefox.

  2. Enter the text about:config into the address bar in Firefox - this is the space where you normally see a website's URL. Make sure not to put any spaces before or after the colon.

  3. A new page will appear that reads "This might void your warranty!" Click or tap I accept the risk!

    This button will read I'll be careful, I promise! if you're using an older version of Firefox. It's always recommended to keep your software fully updated.

  4. A huge list of Firefox preferences should now be displayed. In the search box at the top of the page, enter javascript.enabled.

  5. Double-click or double-tap this entry so that its "Value" changes from true to false.

    Android users should select the entry just once and then use the Toggle button to disable JavaScript.

  6. JavaScript is now disabled in your Firefox browser. To re-enable it at any time, simply return to Step 5 and repeat that action to reverse the value back to true.