> the fact that the tick shows is also a bug. notice the scroll bar.

What do you mean? You're showing no characters in the pane, the
insertion point is after the last character.

Or do you want to have the ability to scroll beyond the end of your
text, to have some imaginary scroll advance taking you out into the
blue past the edge of the world?

Or do you want to disallow scrolling to just past the last character?
How many characters would you say need to remain showing?