type about:preferences into your search bar and check what your home page is. reset it just in case. restart firefox check if tab opens.

try shift-Click firefox to start it. see if that tab still opens. if it doesn't, this means that there is some add-on doing this. type about:addons and see which addon might be doing this. if it still doesn't fix just clear the cache or refresh firefox it should be solved.

mseaboa said

When I load Mozilla Firefox my home page loads OK but a new tab loads also with 'Search or enter address' in the url space where an address should be typed. When I click on Page info under general tab the address for the New Tab is chrome://ntsd-a/content/newtab/newtab.html. I do not want the New Tab to load automatically. How can I stop this action?

To fix my problem I had to refresh Firefox. Thanks very much Zawar..