Fix magic line creating an empty space at the top of the pad

customize.dist/ckeditor-contents.css

@@ -24,10 +24,16 @@ body
     right: 0;
 }
 
+/* Remove margin-top for the first element */
 body > *:first-child {
     margin-top: 0;
 }
 
+/* If the magic line is the first element, remove margin-top for the next one */
+body > .non-realtime:first-child + * {
+    margin-top: 0;
+}
+
 .cke_editable
 {
     font-size: 16px;