"No Connection to Gateway" when using Inline Frame Component

We are doing design of a screen with a vendor and in order to have clearly split responsibilities, we are considering embedding their part (control buttons) in an inline frame.

This seems to work except for this annoying text that shows up.

Because we are getting the view (which is just coming from another project on the same gateway) the message “No Connection to Gateway” seems incorrect given that the view renders and the buttons work. How can I make this go away?