Window.trapKey

Function/Meaning
Whether to trap key input
Type
Window class property (read/write)
Description
Represents whether to trap key input. You can also set this value.
If set to true, key input events occurring in other windows can be intercepted and triggered on this window.
If this property is set to true for multiple windows, the key input event will occur for the window that was created last.
Reference
Window.focusable