cq:showOnCreate not working with RTE on Page properties

We are using an RTE field in the page properties. The issue here is, this field doesn't render in the page properties when author is creating the page. Is this a known issue with AEM? Is there any workaround for this?

 <bannerText
    cq:showOnCreate="{Boolean}true"
    jcr:primaryType="nt:unstructured"
    sling:resourceType="cq/gui/components/authoring/dialog/richtext"
    fieldLabel="Banner text"
    fieldDescription="This text describes the banner message."
    required="true"
    name="./bannerText"
    useFixedInlineToolbar="{Boolean}true">
<rtePlugins jcr:primaryType="nt:unstructured">
    <format
....
<bannerText?>

PS: We are using AEM 6.5

Thanks in advance!