Feature: Able to get active window other properties like positions & states about active-win

[sindresorhus]

Position and size are available for macOS in master, see #19. It's just waiting for implementation on Linux and Window, and docs.

[sindresorhus]

To change the states we can have something like activeWin.state(['minimized', 'maximized', 'normal', 'close']);, and to move current window we can have something like activeWin.move(t,l,b,r);.

That's outside the scope of this module.

[sindresorhus]

Closing in favor of #23

[xudaolong]

@sindresorhus I want to know if can just provide information about activeWin.state instead of manipulating them. Thanks.