Here you are!
Settings: "Fit to content width", "Overlap shading on", "Comics mode on" (as in "CM off" mode "OS on" does almost nothing, except of greying out up to couple of text strings). The pages are tall and don't fit to the screen. The text is black (
screen1.png), we press the "next page" to move to the rest of the page. This rest of the page (the text) is black and the part we have read is grey (
screen2.png). It's all OK. But if we move
backward, to the
beginning of the page, we get the picture, in which only small upper part of the text is black, but the bigger part of it is grey (
screen3.png). All the page should be black because of a human reads from up to down and because of just one page turn before we saw the text in black and because of the grey page looks very uncomfortable.
The reading of miscellaneous handbooks means seeking forward and backward through the book, and such behavior of overlap shading bothers very much and makes overlap shading almost useless.
And it would be nice to turn on "Comics mode" automatically when the "Overlap shading" is on and to return to previous state of "CM", when overlapping is off. And probably to turn off overlapping shadow when we turn off CM. Some kind of AI.