How do you remove a untrusted addon from the prompt to install list?
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.
Alla svar (1)
I found it. Game Play Labs installed an EXTENSION disguised as a Video Codec which was giving the continued prompt to install the plug-in.