Automatically disables another node if not visible on screen. VisibleOnScreenEnabler2D detects when it is visible on screen (just like [VisibleOnScreenNotifier2D]) and automatically enables or disables the target node. The target node is disabled when [VisibleOnScreenEnabler2D] is not visible on screen (including when [member CanvasItem.visible] is [code]false[/code]), and enabled when the enabler is visible. The disabling is achieved by changing [member Node.process_mode]. Determines how the node is enabled. Corresponds to [enum Node.ProcessMode]. Disabled node uses [constant Node.PROCESS_MODE_DISABLED]. The path to the target node, relative to the [VisibleOnScreenEnabler2D]. The target node is cached; it's only assigned when setting this property (if the [VisibleOnScreenEnabler2D] is inside scene tree) and every time the [VisibleOnScreenEnabler2D] enters the scene tree. If the path is invalid, nothing will happen. Corresponds to [constant Node.PROCESS_MODE_INHERIT]. Corresponds to [constant Node.PROCESS_MODE_ALWAYS]. Corresponds to [constant Node.PROCESS_MODE_WHEN_PAUSED.