Inner container more big than outer one

I have a HBoxContainer inside a VBoxContainer. I can increase the HBoxContainer over limits VBoxContainer. How it is possible? Is is a bug?

Same "problem" if I use panel inside a container. I can set the panel bigger than its container:

panel is the one with background black

Thank you

From developer staff the latter it work as intended. The first problem I opened a ticket: https://github.com/godotengine/godot/issues/16886