The browser.newtab.url pref is no longer supported in Firefox 41 and later, so you can no longer use this to set the new tab page.

You can look at this extension to set the new tab page:

• New Tab Override: https://addons.mozilla.org/firefox/addon/new-tab-override/

You can set the new tab URL setting via the Options/Preferences of the extension on the about:addons page.

Look at this extension to use the home page:

• New Tab Homepage: https://addons.mozilla.org/firefox/addon/new-tab-homepage/

Classic Theme Restorer includes this feature as well. In CTR version 1.3.9 you can find the "New tab page url" in the Tabs (1) window.

You can use these special pages for the new tab page or use the URL of a web page. the default new tab page with the tiles is about:newtab

• the default home page is about:home
• for a blank page you can use about:blank
• for Super Start you can use about:superstart

Thank you the homepage add-on worked beautifully. I didn't have to do anything else. Not sure what to do for the first add-on offered, although I downloaded it. Just wished they'd tell us this when they make the change!

You only need one of the extension that set the new tab page, otherwise it might not be clear which set the new tab page. So best is to uninstall the New Tab Override extension. The NTO extension allow to set any page as the new tab page, so you would have to enter the URL of the home page yourself via its Options/Preferences button.

thank you! i will uninstall NTO add-on.