sendmail user@example.com < email.txt mail -s "Test Subject" user@example.com < body.txt
[1] https://stackoverflow.com/questions/57410259/how-to-send-an-...
So if you had aliased "user@example.com" to "bob", you could do:
mutt -s "Test Subject" bob < body.txt
[1] Mutt refers to its address book as "aliases".
`pop --to $(fzf contacts.txt)`
[1] https://stackoverflow.com/questions/57410259/how-to-send-an-...