Window Management Blueprint Specification
Moving windows is a common task on multi-monitor systems Ubuntu needs a way to make this easier and more efficient.
With Custom windows buttons you can move a window to a different monitor with the click of a button.
An example could look something like this:
You can also easily maximize a window to the desktop (stretch it across all monitors).
In addition to custom window buttons, Ubuntu Could also add custom menu commands to the window (or system) menu of applications. The custom menu commands add the same functionality as the window buttons.