Why does the mouse cursor jump a few pixels if you right-click on the Start button?
Some time ago, I noted that mouse cursor jumps a few pixels if you click on the very bottom row of pixels on the taskbar. I noted that this is done to make it possible to click on the very bottom row of pixels, even though they are technically a border, in order to operate on the button immediately above them. Otherwise, the button-down code sees that the mouse is outside the button and cancels the button operation (click or drag).
If you right-click on the Start button, the mouse cursor jumps a few pixels up and to the right. Is this done to solve the same problem?
No, the problem doesn’t apply here because the right mouse button does not have the same cancellation behavior as the left mouse button. There’s a different reason for moving the mouse cursor.
The mouse cursor moves up and to the right so that it is positioned over the last menu item. That way, you can right-click followed by left-click to activate the bottom menu item.
This means that the bottom item on the Start button’s context menu has a special status: It’s the one you can activate quickly by performing a right-click left-click.