A number of Chrome (and I think also Firefox) extensions include their own local copy of OpenPGP.js for use with various webmail services, including GMail.
How does an email client use WKD?
1. A user selects a recipient for an email.
2. The email client uses the domain part of the email address to construct which server to ask.
3. HTTPS is used to get the current public key.
The email client is ready to encrypt and send now.
An example:
https://intevation.de/.well-known/openpgpkey/hu/it5sewh54rxz33fwmr8u6dy4bbz8itz4 is the direct method URL for "[email protected]
A number of Chrome (and I think also Firefox) extensions include their own local copy of OpenPGP.js for use with various webmail services, including GMail.
WKD (and HKP) depends upon HTTPS without cert pinning, FWIU: https://wiki.gnupg.org/WKD