I've spent hours going through every suggested solution to this problem I can find, and this is the only thing that actually fixed it. Only 4 stars because I've found a lot of sites that need the default background to be white. Fortunately the extension lets you exclude those sites. I think it would be better to have the option to work by an opt-in system rather than an opt-out system. I also think it would be good to have an on/off toggle on the icon.