If there is a problem with searching via the default about:home page then try to reset the search engine used on the about:home page.
Reset the browser.startup.homepage_override.mstone pref via the right-click context menu to the default on the about:config page and close and restart Firefox to restore the about:home page to its default.
Re: Yahoo has taken over my search and I want Google back as default search
about:config and downloading DEVONtechnologies EasyFind to destroy the hidden Yahoo files in the Library on a Mac no longer works.
I suspect Yahoo has found a way to undermine those fixes.
It is infuriating to find that a responsible operator such as Yahoo needs to stoop to this to find users to its dying web browser.
Are there any other suggestions? Many thanks