Using AppleScript to set a mail message to Plain Text

Question

I have an AppleScript that nicely collates information and creates an email message with attachments.

I cannot find a way for the script to set the message format to

Answer 1

You can use keyboard shortcut ⌘shiftt also to change the message format to plain text:

tell application "System Events" to keystroke "t" using {command down, shift down}

Tested in Mail version 12.4