Mailvelope support for OpenPGP encryption in webmail
"Mailvelope is an easy-to-use web-browser extension which brings OpenPGP encryption to webmail services such as Gmail™, Yahoo™ and others. With its unintrusive interface fully integrated into your webmail service, Mailvelope instantly secures your personal and professional email communications."
Viktoria Rei Bauer commented
Better than nothing. I'd prefer native GPG/PGP support.