Firefox browser provides large number of add-on to customize and extend the functionality. Firefox is constantly updated and add-on also need to be updated to work with latest Firefox version. You may not able to install add-on if its version is not updated. Follow the below steps to bypass this and force install incompatible Firefox addons.

Force Install Incompatible Firefox Addons

Tips & Warnings

1 First get version of your Firefox browser by doing below steps:

  • Select “Help” in the menu bar and click “About Firefox” in the menu. You will find a new pop-up window displays the Firefox version. For example: Firefox 14.0.1
  • Note down the version, which you need later.

2 Go to Firefox preference window: Type “about:config” in the address bar and hit “Enter”. You will find a small warning box. Click “I will be careful, I promise!” button. Now you will find some list of preferences in the window.

3 Create a new Boolean key. Right-click anywhere on the “about:config” page and select “New”, then click “Boolean”.


4 Type “extensions.checkCompatibility” followed by Firefox version like “extensions.checkCompatibility.14.0.1”. click “OK”.


If the above key name has already exist, then right-click on it and click “Toggle”. This will change the Boolean value to “false”.

5 Choose Boolean value as false and click “OK”. This will remove compatibility check and allows you to install all the add-on.


6 Restart your Firefox browser to save the settings. Now you are able to install incompatible Firefox addons.

Tips & Warnings

  • Installing incompatible add-on may affect Firefox browser to work properly. If you face any issue then immediately uninstall the recently installed add-on. Also restart the browser to protect theme breakage and Firefox data.
  • Use “Skip Addon Compatibility Check” to automatically install incompatible Firefox addons. Just install this add-on and restart your browser. This will automatically create a new key and change its value to false.