Hello King Fox

Thank you for installing Add HTTPS. I am sorry that it did not work for you. If you could let me know your OS, Firefox version and a screenshot of what you're seeing, it will help us a lot to find out what's going on and fix it.

I have just tried it on Firefox 54.0.1 (32-bit) on Windows and everything looks fine. Please share more details and help me reproduce the issue.

I have created an issue for this here: https://github.com/sanspace/add-https/issues/8 You can folow the conversation there too. Thank you.