So, many people want a DARK browser. We want a dark gray or black background, and the load screen to be dark gray or black also. That Flash of white is quite painful when switching between dark websites.
Want to make Opera stand out? make a standard Dark browser that turns white into dark gray.
I know back in the day, the white background was though to be good when the color monitors came out. It made the transition from real paper to computer easier to many, but why the white background is still standard boggles the mind. We would never expect someone to sit and stare into a 40 watt light bulb, so why do we continue to insist on a white background?