How to remove HTTPS EVERYWHERE from Firefox browser

Stupid me and knowing better I downloaded this add-on based on reviews. The first place I tried to go, and one I use frequently, is blocked. Where on my computer can I find where/how to get rid of this without deleting Firefox and re-installing, please. Many Thanks ! for a prompt reply. TN Bob

The three bar option menu -> Addons -> Extensions

I thank you very much, Jerod, for your prompt and accurate reply. I had been to the addons but overlooked the extensions option. Your help is much appreciated. Bob Lambert, TN