Instructions:
1- Click the Firefox icon in the upper left corner of your browser.
2- Hover over Options.
3- Click Options.
4- Click Content tab.
3- Check Block pop-up windows to enable pop-up blocker.
4- Ucheck Block pop-up windows to disable pop-up blocker.
5- Click OK.
How to Disable or Enable Pop-up Blocker in Firefox
http://www.howtodo-video.com/2013/04/how-to-disable-or-enable-pop-up-blocker_8834.html
Autor: How To Do Video
Enlace al vídeo: https://www.youtube.com/watch?v=wdr6H7Dq5Y8