dalanicolai <dalanicolai@gmail.com> writes:
> When I try to use `(set-window-start ...)`, then for some reason subsequently setting `vscroll` does not work.
> Setting vscroll does work after a `(redisplay)` but then the jump becomes very 'ugly'.
That is because the window start will be forced after the next
redisplay. The fix is to pass t as the `noforce' parameter to
`set-window-start'.
If you're interested in this, I suggest to look at some of the code in
pixel-scroll.el.