I have custom remotes on an iPhone and iPad, with a panel that displays the Roon web display in a WebView control. Or at least it used to… After the 2.0 update it no longer works. The webview shows blank (not even the Roon logo) and the device doesn’t appear as an available display in the zone popup.
The port is the same and I can use Safari to open the URL from the same devices, so it isn’t an access or routing problem. Core is running on a Mac Mini/Catalina.