Depends, perhaps, on whether the email client is in rich text mode or plain text mode ?
( The choice of pasteBoard item – public.utf8-plain-text vs public.html or public.rtf – will turn on that )
To see the set of (textually representable) pasteboard types in your clipboard at any given moment, you can use this: Clipboard Viewer
Or to simply see a list of the types, without a view of their contents:
List of pasteboard types currently in clipboard.kmmacros (2.1 KB)
