Handling HTML5 Client Route Fallbacks in ASP.NET Core

HTML5 client routes work great on the client, but when deep linking into a site or pressing refresh in the browser, HTML5 client side routes have a nasty habit of turning into server HTTP requests. Requests to routes that the server is likely not configured for. In this post I look at why HTML5 client routes require server cooperation to handle and how to set them up on IIS and/or ASP.NET Core.