Index: branches/5.3.x/core/admin_templates/js/forms.js
===================================================================
diff -u -N -r16390 -r16595
--- branches/5.3.x/core/admin_templates/js/forms.js	(.../forms.js)	(revision 16390)
+++ branches/5.3.x/core/admin_templates/js/forms.js	(.../forms.js)	(revision 16595)
@@ -134,15 +134,27 @@
 	}
 
 	if ( !$.isEmptyObject($CodeMirrorEditors) ) {
-		var $editor;
-
-		for (var $editor_id in $CodeMirrorEditors) {
-			var $textarea_element = $('#' + jq($editor_id)),
+		$.each($CodeMirrorEditors, function ($editor_id, $editor_options) {
+			var $editor,
+				$textarea_element = $('#' + jq($editor_id)),
 				$height = parseInt($textarea_element.height(), 10);
 
-			$editor = CodeMirror.fromTextArea($textarea_element.get(0), $CodeMirrorEditors[$editor_id]);
+			if ( $textarea_element.is(':disabled') ) {
+				$editor_options.readOnly = 'nocursor';
+			}
+
+			$editor = CodeMirror.fromTextArea($textarea_element.get(0), $editor_options);
 			$editor.setSize(null, $height);
-		}
+
+			$textarea_element
+				.on('change', function ($e) {
+					$editor.getDoc().setValue($textarea_element.val());
+				})
+				.on('refresh', function ($e) {
+					$editor.setOption('readOnly', $textarea_element.is(':disabled') ? 'nocursor' : '');
+				})
+			;
+		});
 	}
 }