The MouseEvent.metaKey
read-only property is a boolean value that indicates whether the meta key was pressed or not when a given mouse event occurs.
Be aware that many operating systems bind special functionality to the meta key, so this property may be false
even when the key is actually pressed. On Windows, for example, this key may open the Start menu.
Note: On Macintosh keyboards, this key is the command key (⌘). On Windows keyboards, this key is the Windows key (⊞).