Dockable container is blocking mouse input to area nodes in a child viewport

[gilzoide]

Dockable container is blocking mouse input to area nodes in a child viewport

[MaxKablaam]

I was able to get this to work by adding this line to a script on the top level node:

func _input(event):
	$DockableContainer/MarginContainer/ViewportContainer/Viewport.unhandled_input(event)

Maybe I missed this documented somewhere, but it would be helpful for others.
Perhaps there could be a checkbox in the dockable container that can handle this, so that it is more user friendly.

[gilzoide]

Unfortunately, this is a known unintuitive behaviour of Viewports + ViewportContainers in Godot, in a quick search I found two open issues about it (godotengine/godot#17326, godotengine/godot#26181) =(

You can also move this workaround to your ViewportContainer and handle this in _gui_input like in this answer if you want, it may be a little better than making your top level node have this responsibility.

Perhaps there could be a checkbox in the dockable container that can handle this, so that it is more user friendly.

Apart from ViewportContainers, that are explicitly made to handle Viewports, it doesn't make sense trying to track Viewports as an edge case on general purpose Containers like DockableContainer.