GUAC-1043: Position viewport and menu absolutely, not with fixed. This also solves some iOS issues with the rendering of fixed elements after rotation.

guacamole/src/main/webapp/app/client/styles/menu.css

@@ -22,7 +22,7 @@
 
 #menu {
     overflow: auto;
-    position: fixed;
+    position: absolute;
     top: 0;
     bottom: 0;
     max-width: 100%;