When working with HTML for emails, there are some quirks—especially due to Microsoft’s legacy rendering engines (e.g., Outlook using Word). As a result, valid email HTML often includes conditional comments and XML namespaces, such as:

<!--[if mso]>
<noscript>
  <xml>
    <o:OfficeDocumentSettings>
      <o:PixelsPerInch>96</o:PixelsPerInch>
    </o:OfficeDocumentSettings>
  </xml>
</noscript>
<![endif]-->

However, this gets transformed into:

<!--[if mso]><noscript><xml><o:officedocumentsettings><o:pixelsperinch>96</o:pixelsperinch></o:officedocumentsettings></xml></noscript><![endif]-->

The casing of tags and attributes inside the xml block is being incorrectly lowercased, which breaks compatibility with Outlook. I would expect the output to preserve the original casing, like this:

<!--[if mso]><noscript><xml><o:OfficeDocumentSettings><o:PixelsPerInch>96</o:PixelsPerInch></o:OfficeDocumentSettings></xml></noscript><![endif]-->

Would it be possible to prevent this lowercasing behavior, or allow casing to be preserved in specific blocks like this one?