The options that will be used for the popup initialization. For more details about the available options refer to Popup documentation.

Example - append the popup to a specific element

<div id="container">
    <input id="dropdowntree">
</div>
<script>
$("#dropdowntree").kendoDropDownTree({
  dataSource: [
    { id: 1, name: "Apples" },
    { id: 2, name: "Oranges" }
  ],
  dataTextField: "name",
  dataValueField: "id",
  popup: {
    appendTo: $("#container")
  }
});
</script>
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