Fix the splitter in code and add it back

www/code/inner.js

@@ -437,35 +437,35 @@ define([
             });
 
 
-/*
+
             // add the splitter
-            if (!$iframe.has('.cp-splitter').length) {
-                var $preview = $iframe.find('#previewContainer');
+            if (!$('.cp-splitter').length) {
                 var splitter = $('<div>', {
                     'class': 'cp-splitter'
-                }).appendTo($preview);
+                }).appendTo($previewContainer);
 
                 $preview.on('scroll', function() {
                     splitter.css('top', $preview.scrollTop() + 'px');
                 });
 
-                var $target = $iframe.find('.CodeMirror');
+                var $target = $('.CodeMirror');
 
                 splitter.on('mousedown', function (e) {
                     e.preventDefault();
                     var x = e.pageX;
                     var w = $target.width();
 
-                    $iframe.on('mouseup mousemove', function handler(evt) {
+                    $(window).on('mouseup mousemove', function handler(evt) {
                         if (evt.type === 'mouseup') {
-                            $iframe.off('mouseup mousemove', handler);
+                            $(window).off('mouseup mousemove', handler);
                             return;
                         }
                         $target.css('width', (w - x + evt.pageX) + 'px');
+                        editor.refresh();
                     });
                 });
             }
-*/
+
 
             Cryptpad.removeLoadingScreen();
             setEditable(!readOnly);