I'm using IE11 (latest update) and Win10. Edge is not actually IE, I'm not really sure what it is but both IE and Edge came with my Win10 system. Anyway, I have no issues with scrolling at all. There are still the odd threads that don't 'auto fit' the screen and I have to scroll sideways to view them, but apart from that everything works fine.
I'd like to be a perfectionist, but I lack the patience...not to mention the skill...