Neomutt Commander

Create ~/.config/neomutt/neomuttrc (or ~/.neomuttrc):

set imap_user = "user@gmail.com"
set imap_pass = "*"
set folder = "imaps://imap.gmail.com:993"
set spoolfile = "+INBOX"
set ssl_force_tls = yes
set imap_keepalive = 300
set mail_check = 60
set postponed = "+[Gmail]/Drafts"
set sort = reverse-date
HTML handling
auto_view text/html
alternative_order text/plain text/html

For other providers change imap.gmail.com:993 and [Gmail]/Drafts to match your server. For Gmail, imap_pass should be an App Password (Google Account → Security → 2-Step Verification → App Passwords).

Create ~/.config/neomutt/mailcap so w3m renders HTML parts:

text/html; w3m -I %{charset} -T text/html; copiousoutput;