Prevent http referer and clipboard leaks
Go to your search engine input query "what is my referer" click on any result, it gives your previous destinations.
Disable clipboard leaks to prevent javascript based spying and other search engines leaks.
Please set these prefs as
keyword.enabled to false dom.event.clipboardevents.enabled to false network.http.referer.XOriginPolicy to 2 network.http.referer.XOriginTrimmingPolicy to 2