Coming soon: email@example.com will work, from this page or your mail client.
The keybase program is open source and uses both GPG + the Keybase identity proofs API. It's great, and you don't have to worry whether your browser or extensions have been compromised.
keybase encrypt -m "message" [them]
You may import from Keybase to GPG easily and then perform whatever cryptographic actions you want.
# using curl curl https://keybase.io/[them]/key.asc | gpg --import # using keybase track, which imports to GPG and # also audits and displays identity proofs keybase track [them]