A quick follow up : are you telling about safe search toolbar or safe search (comes during search) If this then off this setting as suggested here,but it may be gives you some inappropriate results too ,so keep care .[https://support.google.com/websearch/answer/510?source=gsearch&hl=en] Else if you are telling about toolbar then use following steps to remove it from firefox : Press CTRL+SHIFT+A simultaneously and enter . this will opens addon tab where you need to go to extension and look out for any possible existance of safe search toolbar. If it present there then remove it completely and restart your browser. Now You also need to scan your system with some good malware scanner like [https://www.malwarebytes.org/ Malwarebytes] or [http://www.surfright.nl/en/hitmanpro Hitman] also [https://toolslib.net/downloads/viewdownload/1-adwcleaner/ Adw Cleaner] . A similar question were asked here : https://support.mozilla.org/en-US/questions/996812 So you can also check for further reference . one suggestion (not related with this problem directly,but recommended): You are using an outdated version of flash player , so you need to update it for maximizing security .