Currently, it looks like when loading content into the XamRichTextEditor from HTML using the HtmlDocumentAdapter, only specific types of elements are preserved, such as images, tables, paragraphs, etc. However, HTML elements that don't map to visible content, such as those with "display: none;" in their style, or elements with a "hidden" attribute, or any empty tags, are not preserved; therefore, this content is lost when serializing the document content back to HTML. 

It would be really useful for the XamRichTextEditor to preserve all HTML content when loading it into the XamRichTextEditor, rather than only content that would be visible in the editor. Or at the very least, it would be useful for the XamRichTextEditor to support the "display: none;" style.

Thanks!