Editor: Avoid compiling when changing contents.

editor/js/Script.js

@@ -71,6 +71,8 @@ var Script = function ( editor ) {
 	codemirror.setOption( 'theme', 'monokai' );
 	codemirror.on( 'change', function () {
 
+		if ( codemirror.state.focused === false ) return;
+
 		clearTimeout( delay );
 		delay = setTimeout( function () {