These pop-ups within Chrome and Firefox shows you are infected with adware or potentially unwanted program. Follow the steps below even if you are not seeing the pop-ups now.
- Remove Adware and PUPs with these free tools. Check for updates first and then scan with each one at a time until your computer is clean. AdwCleaner http://www.myantispyware.com/download/adwcleaner, JRT (Junkware Removal Tool) http://www.myantispyware.com/download/jrt , MalwareBytes Anti-Malware from http://www.myantispyware.com/download/malwarebytes-anti-malware
- Reset Chrome and Firefox. For Firefox http://www.myantispyware.com/2016/02/07/how-to-reset-mozilla-firefox-settings-to-default/ , for Chrome http://www.myantispyware.com/2016/01/06/how-to-reset-google-chrome-settings-to-default/