When clicking on the vertical scrollbar below the scroll box (or "thumb"), FASMW scrolls down a full screen page. If less than a full screen page is left, FASMW
should display that last page entirely. However, that does not happen. Instead, if less than a full screen page is left, FASMW starts to scroll down line-by-line.
Apart from being unexpected, that behavior is also a little annoying with bigger monitors, because scrolling down the last 30-40 lines may consume a lot of time.
Fortunately there appears to be a simple fix, it requires changing one single line in SOURCE\IDE\FASMW\ASMEDIT.INC:
vscroll_pagedown:
mov esi,[window_line]
mov eax,[sc.nPos]
add eax,[sc.nPage]
mov ecx,[sc.nMax]
sub ecx,eax
inc ecx
cmp ecx,[sc.nPage]
; jbe scroll_down ; original code
jbe scrolling_down ; new code
mov ecx,[sc.nPage]
scrolling_down: