This would be an inconvenience because Firefox is updated every month which means you’ll need to recreate a new preference name on every major release.

However since version 3.6, Firefox requires you to include the application version at the end of the preference. On older versions of Firefox, it is possible to easily disable add-on compatibility checks by simply toggling the extensions.checkCompatibility preference from the about:config to false. Please ignore the the warning message that is shown in the Add-ons Manager telling you that the compatibility checking is disabled and you may have incompatible add-ons. Go to the Add-ons Manager window by pressing Ctrl+Shift+A, right click on the incompatible add-on and select Enable. After installing the extension, restart your Firefox web browser, press Alt+T to show the menu bar, go to Nightly Tester Tools and select “ Force Addon Compatibility“.Īfter enabling the force addon compatibility option, you can now forcefully enable an incompatible addon. The Nightly Tester Tools is an extension for Firefox which has the ability to disable add-on compatibility checking. Here we have 4 ways to force the installation of incompatible extensions in Firefox. However there are times when it reports that the extension is incompatible with Firefox or you cannot install because the Add to Firefox button is grayed out with a text saying not available for Firefox. This is actually a safety feature to allow the extension developers to fully test and verify that their extension is compatible with the latest Firefox and not crashing it. Currently there is more than a whopping 12,000 extensions that can be installed on the current Firefox.Īlthough the extensions are very useful, the constant browser updates which are released every month can cause some of the extensions to stop working if they are programmed to only run with specific versions of Firefox. One of the most impressive features found on both of those web browsers is the amount of available free extensions or add-ons that you can download and install to modify the existing behavior of the browser or even add new features such as a FTP client (FireFTP), download manager (DownThemAll!), or advertisement blocker (Adblock Plus) without requiring a dedicated third party software.

Google Chrome and Mozilla Firefox are the most used web browsers today.

How to use older versions of firefox