update

js/Desktop/DeskTop.js

@@ -6277,9 +6277,13 @@ U.MD.D.I.openApplicationJie = function (str, cid, stage, task, tool) {
         } else if (str == 'whiteboard') {
             _iframe = _formdiv.querySelector('iframe')
             let onloadListener = _iframe.onload = () => {
-                alert(_box.offsetWidth)
-                alert(_iframe.offsetLeft)
-                alert(_iframe.contentWindow.document.body.innerHTML)
+                try {
+                    alert(_box.offsetHeight)
+                    alert(_iframe.offsetHeight)
+                    alert(_iframe.contentWindow.document.body.innerHTML)
+                } catch (error) {
+                    alert(error)
+                }
                 _iframe.contentWindow.document.body.appendChild(script1);
                 _iframe.contentWindow.document.body.appendChild(script2);
                 _iframe.contentWindow.document.body.appendChild(script4);