In your case the exec function of the custom tool should perform something like this:
var editorContent = $(this).data("kendoEditor").document.documentElement.outerHTML,
win = window.open(),
doc = win.document;
doc.write(editorContent);
doc.close();
win.print();
Note that opening a new browser window may be prevented by the browser. You can consider outputting the Editor's content in the current window, which would replace the page content.
All the best,
Dimo
the Telerik team
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