completely change the CSS to be an entirely 'position: absolute' layout rather than top-to-bottom. makes the overscroll much more predictable and sane and not dependent on CSS expressions.

webclient/app.js

@@ -70,4 +70,9 @@ matrixWebClient
                 $timeout(function() { element[0].focus() }, 0);
             }
         };
-    }]);
+    }])
+    .filter('to_trusted', ['$sce', function($sce){
+        return function(text) {
+            return $sce.trustAsHtml(text);
+        };
+    }]);