You may have an unwanted extension that is generating the ad popups. Try this: Disable ALL nonessential or unrecognized extensions on the Add-ons page. Either: * Ctrl+Shift+a * orange Firefox button (or Tools menu) > Add-ons In the left column, click Extensions. Then, if in doubt, disable. Or remove. Usually a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step. Does that eliminate the popups? ---- If you find extensions that do not have a Remove button, usually this indicates that they were installed externally. Check the Windows Control Panel, Uninstall a Program. Click the "Installed on" column header to bring recent additions to the top and reveal items that were bundled together, perhaps without your knowledge. To mop up, you can try the scanners in this support article: [[Troubleshoot Firefox issues caused by malware]].