Here's another issue that I'm discovering (if you prefer I open new threads for any new issues, let me know). With 'Settings -> Postie -> Message -> Preferred Text Type = HTML', the following behavior is what I've observed Postie reporting when testing with various types of emails (manually pressing "Run Postie" from the settings screen):
Sending a Plaintext-only email, Postie reports "primary= text, secondary = plain"
Sending an HTML-only email, Postie reports "primary= text, secondary = html"
Sending a Plaintext + HTML email, Posite reports "primary= multipart, secondary = alternative"
Since "Preferred Text Type = HTML", shouldn't the HTML-only email set the primary text type to HTML instead of text? Or am I misunderstanding something about what Postie is reporting?