Decrypted text does not replace the message body if the Formatting toolbar is
displayed. Instead, the plaintext is visible in the "Font Size" dropdown for a
split-second.
I was able to get a "Task Pane" in Outlook once (can not seem to get it again),
and when that was open the decrypted text was going in the first text field in
that pane.
Is gpgol just putting the text in the first RichEdit window it finds?