Viewport and accessbility focus. Bug or intentional behaviour?

Hi, I have a main component containing a viewport on the left and a component on the right. The viewport contains a wide component. Both components contain a set of buttons and sliders numbered accordingly. When navigating on the right component with voiceOver enabled I am able to access the buttons and sliders of the viewport’s component. Is this an intentional behaviour? Isn’t the purpose of a viewport to show a section of the component it owns?

Viewport problem gif