Earlier quoted context omitted.
> that is what PgUp/PgDown are for on the keyboard, no? Definitely no: If I have a hand on the mouse I surely don't want to lift it and hunt for the PgUp or PgDown just to move one page up or down. And no, I don't want to go "there" if it's actually "somewhere" in the middle of whatever, if I just want to see the previous or the next page. Going "there" is much less frequent operation than moving to the next or the p…
So, that means a PgDown button (I guess it is mostly that direction) on the mouse is missing. The thumb button which most mice have and are mapped to forward/backwards could be remapped to that. Or a mouse gesture? FoxyGestures, a Firefox addon, has a "Scroll Down" action.
"Most"? Where did you get that idea? "Most gaming mice" or what? Most of the users aren't gamers.
> that means a PgDown button (I guess it is mostly that direction) on the mouse is missing.
Of course is missing: "normal" (as in the most common) mice have only 2 buttons and the scroll wheel.
The scroll wheel never moves one page up (or down), but just some small number of lines, so the most common operation is then impossible for the most of the users just because a developer (who probably even "lives" in his terminal for most of the time, never lifting the both hands from the middle of the keyboard) thinks that everybody has exactly the gear that he has.