Firefox had extensions way before Chrome did and the repository gets better all the time but what’s stuck around in Firefox for quite a while is the extension install delay of seconds. The delay, you might be hard put to discover, exists for a security reason. It prevents users from automatically clicking on dialog boxes that execute hidden commands that could install malware. The chances of this happening are higher for people who spend copious amounts of time online and are termed as ‘fast clickers’. For the truly cautious users, there’s a way to remove the install delay so long as you’re careful about not installing extensions from shady developers. No XPI Install Delay is a Firefox extension that will remove the install delay allowing you to simply click Install and proceed to install the extension.
The extension tweaks a preference in about:config, you could do it too but for those of you looking to find an easy way this extension will make the necessary tweaks. If you want to check the tweak out yourself, go to about:config and search for security.dialog_enable_delay. The extension changes the value to 0 thus ending the install delay. Since the delay only works on extensions installed from the Firefox repository and not on other sites, the delay itself loses some of its purpose. Remember to practice caution no matter what it is you download and where you download it form.
Install No XPI Install Delay Extension For Firefox