added iframe support

YongeStreet/Views/Home/City.cshtml

@@ -10,7 +10,7 @@
 </div>
 
 <div class="uk-height-large uk-flex uk-flex-center uk-flex-middle uk-background-cover uk-light" 
-     style="background-color: black"
+     style=""
      id="leaflet-map"
      data-city="@Model.City">
 </div>

YongeStreet/wwwroot/js/site.js

@@ -1,4 +1,20 @@
-// Please see documentation at https://learn.microsoft.com/aspnet/core/client-side/bundling-and-minification
+
-// for details on configuring this project to bundle and minify static web assets.
+const state ={height: -1, url: ''};
 
-// Write your JavaScript code.
+function urlWithoutOrigin(url){
+  return url.replace(new URL(url).origin, "");
+}
+
+function sendEvent(){
+  const height = document.documentElement.offsetHeight;
+  const url = urlWithoutOrigin(document.URL);
+  if(height === state.height && url === state.url){
+    return;
+  }
+  state.height = height;
+  state.url = url;
+  const event = {... state};
+  window.parent.postMessage(event, "*");
+}
+
+window.setInterval(sendEvent, 100)