That's an unjustified excuse. The one thing that is consistent with UI programming among all platforms is that you never block the UI thread. You should be abl

That's an unjustified excuse. The one thing that is consistent with UI programming among all platforms is that you never block the UI thread. You should be able to mock fetch/xmlhttprequest at any point, not just in your router. You should be able to mock those calls without needing to block the UI thread at runtime.