prefixOptions.separator Boolean (default: true)

If set to false, the prefix adornment will not have a separator.

Example - specify prefix adornment separator

<input id="autocomplete" />
<script>
  $("#autocomplete").kendoAutoComplete({
    dataSource: [
        { id: 1, name: "Apples" },
        { id: 2, name: "Oranges" }
      ],
    dataTextField: "name",
    prefixOptions: {
      template: () => `${kendo.ui.icon("search")}`,
      separator: false
    }
  })
</script>