Hi Yositimy,
This works for me, but there is a hitch. It seems windows can't be split across the menu bar from the bottom.
This means two things.
1) The window I'm dragging must fit vertically in the upper screen. If the top screen is smaller than the lower screen I can't drag a "full height" window up as it won't fit. Shorten the window so it fits the upper screen.
2) As I'm dragging, I don't see the window split and move like I do when dragging a window to a side monitor. I need to keep holding the mouse and "dragging" high enough for the window to completely fit in the upper window. Then the window will jump from the lower screen to the upper screen. As I'm dragging, it looks like the window is stalled, blocked by the menu bar until the cursor is high enough.
Interestingly, the window does split across the menu bar when moving it back down, but I can't resize the window to span across the screens unless it's already split by dragging from the top. If the window is completely in the top screen, that is the height limit.
ivan