All this add-on does is is set the new tab page to a blank page (about:blank) rather than the usual new tab page with the thumbnails and search box, to make up for the removal of the 'browser.newtab.url' preference in Firefox 41. If you are using Firefox 61 or later, you don't need this add-on. Instead, open the Firefox Settings page, click the "Home" section at the side, and change the "New tabs" option to "Blank Page". No settings to configure. Code totals 146 bytes of HTML, no JS (version 2.1.0).