Yes you can.

note that you can change the order of the boxes on the about:newtab page and drag an item to a different tile to pin it to that position or you can remove a website by clicking the close X to block that URL. You can drag a bookmark or history item from the sidebar and drop it in a tile on the about:newtab page to pin this item and have your own favorites sites present. Changes made manually on the about:newtab page are stored in prefs that you can find on the about:config page. *browser.newtabpage.pinned stores websites that you have pinned to a tile. *browser.newtabpage.blocked stores websites that you have removed by clicking the X button in a tile. You can reset a pref via the right-click context menu to the default value. See also these articles about the New Tab page (about:newtab): *https://support.mozilla.org/kb/new-tab-page-show-hide-and-customize-top-sites *https://support.mozilla.org/kb/hide-or-display-sites-new-tab-page

Thanks for the responses; question resolved.