Originally Posted by sej7278
kindle pc/kobo desktop/fbreader handle this just fine.
would disabling line-based scrolling fix the issue, as i never use that?
There's no way to "disable line based scrolling" without completely changing how the reader works.
calibre's viewer supports the huge variety of html+css that it does by reusing a browser rendering engine to power it. In that case there are only three possibilities
1) Support only page based rendering
2) Support line+Page based rendering with the occasional line cut off
3) Do an extensive rewrite of the rendering engine (an option that would take man-months of time)