This seems to make it very sluggish.

before:

after:

see how the scroll area isnt keeping up with the mouse?

Tested various implementations using doubles, floats, longs. For me the performance was about the same in all cases. May be it is test configuration dependent.

And about scrolling itself: actually area is not catching cursor - it catches the line to which cursor points at file image. For the very large files it is more noticeable. Were the files in your test of the same length and with the same 'Pixels Per Line' used?

Hopefully this gets fixed soon, because the scrolling area "floating" under cursor for large files is really annoying.

Any updates, guys? :)

Thanks for the PR, sorry it took so long to get it shipped. I'll cut a new release now.