When a web-site tries to load an addon, you get a prompt which clearly says only allow addons from trusted sites. This is clearly an '''UNTRUSTED''' addon (already prompting for installation with suspicious behavior), which I do not want ever installed. So I did not click the "Allow" button and just exited the prompt window. Now the prompt returns for every website, with just the requesting site name being changed. There is no doubt in my mind that this is malware, but I can't find a way to get Firefox to stop asking me to allow its installation.