In the recent versions of the Mozilla Firefox web browser, they have made a strict policy of not allowing any unsigned add-on to be used in the browser. First of all any unsigned add-on is not allowed to be installed, and even if such add-ons are automatically installed in Firefox then those add-ons are disabled by Firefox if they are not signed. This is a welcome step from Firefox as this boosts the browser security by disabling any suspicious add-ons that might be installed by malicious software. But if you must use some unsigned add-on because the developer of the add-on has not released any signed add-ons yet and your work depends on that older unsigned add-on.
Here is how you can quickly enable unsigned add-ons in Mozilla Firefox:
- Open Firefox web browser, type about:config in the address bar and press Enter.
- Click on the I’ll be careful, I promise button to continue. It is possible that this button is not displayed and you are taken directly to the Firefox configuration manager.
- Type signatures in the search box to narrow down the preferences we are interested in.
- Double-click on the preference named xpinstall.signatures.required to switch its value from true to false.
- Close all the Firefox web browser windows and then start it all over again. Go to Add-ons Manager screen by typing about:config in the address bar and pressing Enter.
- Now you would see that there is an Enable button against unsigned add-ons. You can click on this Enable button to enable that add-on and start using them.
- Depending on the add-on you may have to restart the browser for using the newly enabled add-ons.
Even though Firefox allows you to use unsigned add-ons, it must be noted that doing so is a security risk as some malicious programs might take advantage of this and push their malicious add-ons into your Firefox browser.