It could be one of your add-ons, or even add / mal-ware. Look thru your add-ons list and make sure you know what each one is there for. Also, check the programs that are on your computer '''Windows:''' Start > Control Panel > Uninstall Programs. '''Mac:''' Open the "Applications" folder '''Linux:''' * [http://www.freesoftwaremagazine.com/articles/see_all_your_installed_applications_ubuntu_unity Ubuntu Unity]''' {web link} * Xfce: Applications Menu category sections * options depends on the package manager and the desktop environment Go thru the list. If you find something that you don't know what it is, use a web search. '''''[https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware Troubleshoot Firefox Issues Caused By Malware]''''' {web link}

'''Download the [https://addons.mozilla.org/en-US/firefox/addon/searchreset/ Mozilla Search Reset]''' {web link} This add-on is very simple: on installation, it backs up and then resets your search preferences and home page to their default values, and then uninstalls itself. This affects the search bar, URL bar searches, and the home page.