Pales beside Pop-up Controller. Pop-up Controller was a click-on-click-off (toggle) Extension that just worked and worked just that simply--click on, click off. No opening a menu every time one wishes to block or unblock a pop-up. On some sites, pop-ups have to be allowed in order to download applications, updates, firmware, etc. Popup Blocker (strict) is just too much of a hassle compared to Pop-up Controller. Unfortunately, Pop-up Controller won't work with the newer versions of Firefox; so, in moving forward, we are forced to take a step backward.
Modify Popup Blocker (strict) to it as simple to use as Pop-up Controller, with the toggle on/off option, and maybe I'll use Popup Blocker (strict).