This extension replaces the default new tab window with a single-color (customizable in options) screen.
NewTab Color Void is a bare-bones extension that replaces the default new tab window with a single-color (customizable in options) screen. Requires no permissions from the user; doesn't have access to browsing information, Chrome tabs, or anything else.
Source available here: https://github.com/cryptogramber/NewTab-Color-Void