Great work already! I do have one nitpick, however. Instead of handling click events, it seems to be using a more direct mouse input and acting on the mouse but

Great work already! I do have one nitpick, however. Instead of handling click events, it seems to be using a more direct mouse input and acting on the mouse button being pressed. In webpages, this is the difference between onmousedown and onclick events. This is extremely frustrating, perhaps it was done to give the illusion of speed, or it's a side-effect of the immaturity of the GUI framework? If you click and hold on the tab close button on your browser, and then move your mouse away and depress the button, you have the possibility to abort the action. Another side effect of this seems to be that the GUI does not respond to presses from a touchscreen (on laptops), which does not behave like a mouse input, but still fires click events that most applications happily accept.