I'm filing this under web inspector, as I feel that's most appropriate, but please move if you need to. The responsive design mode seems to be missing the iPhone X. It's missing presence is an important limitation in experimenting and testing insets while developing websites.
(In reply to Derk-Jan Hartman from comment #0) > I'm filing this under web inspector, as I feel that's most appropriate, but > please move if you need to. > > The responsive design mode seems to be missing the iPhone X. It's missing > presence is an important limitation in experimenting and testing insets > while developing websites. This is a known limitation. In the meantime, you can use iOS Simulator to get accurate rendering with safe areas and mobile-specific viewports.