Hi, Eduardo -
There is no rule that adjacent monitors must produce a virtual screen/desktop that encompasses only the viewable space of the monitors. The positioning of the viewable space of each monitor within the virtual screen is configurable by the user. You should not assume that all two-monitor configurations are identical to how yours is configured, as there may very well be non-displayable areas within the virtual screen.
For example, two monitors side-by-side, but different makes/models. What would be the result with what you propose if the monitor on the right has a smaller vertical resolution than the one on the left and they are configured to align along the top? The answer is that the lower portion of the window on the right-side monitor will be cropped (not visible), possibly hiding the response window's response button(s).
I caution you regarding what you have proposed because it may not work as you intended in all circumstances. The link below to a Microsoft Windows help topic contains an explanation of the virtual screen and includes an illustration:
https://learn.microsoft.com/en-us/windows/win32/gdi/the-virtual-screen
Best regards, John
Best regards.