Brief summary of issue / Description of requested feature:

When scrolling with your mousewheel in a TConsole("main" or any MiniConsole"), when almost all the way to the top of the scrollback, it is difficult in some circumstances to get the very top line to display. If you end up scrolling with the mousewheel to the second line from the top, scrolling further with the mousewheel will sometimes not take you to the top line without moving the mouse around within the widget.

Steps to reproduce the issue / Reasons for adding feature:

1. Generate enough lines in "main" that you can split the window.
2. Scroll up to split the window.
3. Scroll manually using the scrollbar, or using pageup or pagedown until you're scrolled to the second line from the top.
4. Continue attempting to scroll up using the mousewheel without moving the mouse, observing that it likely will not scroll up to the very first line.

Error output / Expected result of feature

After scrolling high enough that there are fewer remaining lines to go than the wheelscroll should scroll, the next scroll should bring the window to the top. Instead, it appears to get stuck unable to scroll to line 1 until you move the mouse considerably? Unsure exactly what is causing it to allow the final line to be scroll to, but if it isn't scrolling and you leave the mouse in exactly the same spot, it refuses to scroll above the top.

Extra information, such as Mudlet version, operating system and ideas for how to solve / implement:

Was able to reliably reproduce this issue in both Win10 and Ubuntu. Occurs in both "main" and MiniConsoles, so it's presumably an issue in the wheel handling of TConsole.