Back in my Mozilla days, I had a user.js file with the following entries to selectively BLOCK popups from certain sites. It doesn't work in Firefox and I think the configuration commands have been eliminated. I'm in the process of searching the Mozillazine forum, but can anyone tell me how to accomplish what I want to do.
The Firefox Options allow me to block ALL popups and enter exceptions for the ones I want to allow. Not only do I not want to do that, but I don't know all the ones I want to allow. Can I do the reverse and is an extension the "today" answer? TIA...