Find it easier to read black text on a white background? YES. David Passell shares this, "if you use Firefox, there is another good trick which I find even more useful for those websites with garish colors and text and photos spread over (and sometimes off the sides) of the screen.
In the top menu click on view.
Then scroll down to Page Style.
Click on Page Style and in the menu presented (to the right) you will see
No Style and Basic Page Style (the default).
Click on No Style.
The page will change to a more 'linear' presentation. The pictures will still appear as intended, but odd colors and white on black text will be black on white. You will have to scroll up and down to find various links, but not side-to-side when things are off the screen. You can also print the page and not waste a lot of black ink. Try it on our PMUG newsletter.
Unfortunately, I could find no equivalent option for Safari."
And David reminds us about a previous post about Safari where we had said, "One site came up with those tiny white letters on a black background, so that’s when you can do Command and Option and Control and the number 8 to toggle over to readable text, then toggle back."