oledragdrop - How to handle drag and drop of emails and attachments from New Outlook to native (Delphi) application? - Stack Ove

When dragging an attachment from the New Outlook to Windows Explorer the file gets dropped* at that location, when dragging an email from the New Outlook to Windows Explorer, the file gets dropped* at that location after dismissing a security warning in Outlook. (* dropped means it gets copied from %temp%\chrome_drag_<pid of webview2 exe>_<somenumber>\ to its final destination.)

I want to handle those drops in my Delphi application. I have a droptarget, but when enumerating the data formats I get the following:

1. DragContext
2. DragImageBits
3. chromium/x-renderer-taint
4. CF_HDROP
5. Chromium Web Custom MIME Data Format

I can parse the last format, it gives me ids which I assume can be used to download the email or attachment via Microsoft Graph, but that requires interaction with Microsoft Graph, Windows Explorer doesn't need that and I don't want to.

My hopes are with CF_HDROP, but dataObj.GetData fails with a DV_E_FORMATETC error code.

My code:

procedure TSACustomDropTarget.DoDrop(const dataObj: IDataObject; grfKeyState: Integer; pt: TPoint; var dwEffect: Integer);
var
  lFormat: TFormatEtc;
  lMedium: TStgMedium;
begin
  lFormat.cfFormat := CF_HDROP;
  lFormat.ptd := nil;
  lFormat.dwAspect := DVASPECT_CONTENT;
  lFormat.lindex := -1;
  lFormat.tymed := TYMED_HGLOBAL;

  if dataObj.GetData(lFormat, lMedium) = S_OK then // Returns DV_E_FORMATETC, but dataObj.GetQueryData(lFormat) returns S_OK
  begin
    // Get files using DragQuery...
  end;
end;

How can I get CF_HDROP to work, or is there another way to get the file from New Outlook?