title: Failed to read the 'selectionStart' property from 'HTMLInputElement':
body: <p>I'm using binding handler.if i remove this code my code is saved.but if i use 
  this code it will throw error.</p>
  
  <p><strong>Uncaught InvalidStateError: Failed to read the 'selectionStart' property from 'HTMLInputElement': The input element's type ('checkbox') does not support selection.</strong>      </p>
  
  <pre><code> ko.bindingHandlers.wysiwyg = {
          init: function (element, valueAccessor, allBindingsAccessor) {
              debugger;
              var options = allBindingsAccessor().wysiwygOptions || {};
              var value = ko.utils.unwrapObservable(valueAccessor());
  
                      //value = value.text();
              //var v = value[0].childNodes[0].data;
              var $e = $(element);
  
              $.extend(true, {
                  initialContent: value
              }, options);
  
              $e.wysiwyg(options);
  
              //handle the field changing
              function detectFn() {
                  var observable = valueAccessor();
                  var newvalue = $e.wysiwyg("getContent");
                  observable(newvalue);
              }
  
              var current = $e.wysiwyg('document');
              var timer;
              current.bind({
                  keyup: function () {
                      clearTimeout(timer);
                      timer = setTimeout(detectFn, 1000);
                  }
              });
  
              //handle disposal (if KO removes by the template binding)
              ko.utils.domNodeDisposal.addDisposeCallback(element, function () {
                  $e.wysiwyg('destroy');
              });
  
  
          },
          update: function (element, valueAccessor) {
              var value = ko.utils.unwrapObservable(valueAccessor());
  
              $(element).wysiwyg("setContent", value);
              ko.bindingHandlers.value.update(element, valueAccessor);
          }
      };
  </code></pre>