diff --git a/game/index.html b/game/index.html
index 7f49a8b910..6d7ea02aae 100644
--- a/game/index.html
+++ b/game/index.html
@@ -11,7 +11,11 @@
         run();
     </script>
 </head>
-<body>
-	<h1 id="loading">Loading...</h1>
+<body style="background-color:black;">
+	<div id="loading" style="color:white;">
+		<h1>Loading... this may take up to 30 seconds</h1>
+		<h2>If you think something has broken, check your browser's developer console (Ctrl+Shift+I or similar)</h2>
+		<h3>Your browser must support WebGL or WebAssembly.</h3>
+	</div>
 </body>
 <html>
diff --git a/widgetry_demo/index.html b/widgetry_demo/index.html
index e59c8804f4..b0004a9b79 100644
--- a/widgetry_demo/index.html
+++ b/widgetry_demo/index.html
@@ -11,7 +11,11 @@
         run();
     </script>
 </head>
-<body>
-	<h1 id="loading">Loading...</h1>
+<body style="background-color:black;">
+	<div id="loading" style="color:white;">
+		<h1>Loading... this may take up to 30 seconds</h1>
+		<h2>If you think something has broken, check your browser's developer console (Ctrl+Shift+I or similar)</h2>
+		<h3>Your browser must support WebGL or WebAssembly.</h3>
+	</div>
 </body>
 <html>
