Hi, You can turn it off by deselecting '''Remember search and form history''' in '''Tools''' ('''Alt''' + '''T''') > '''Options''' > '''Privacy'''. [https://support.mozilla.org/en-US/kb/Options%20window%20-%20Privacy%20panel?as=u Options > Privacy] To delete the existing entries, click '''Tools''' > '''Clear Recent History''', choose '''Everything''' in '''Time range to clear''', '''Search & Form History''' under '''Details''' and '''Clear Now'''. [https://support.mozilla.org/en-US/kb/Clear%20Recent%20History Clear Recent History].