http://www.w5j6stm77zs6652pgsij4awcjeel3eco7kvipheu6mtr623eyyehj4yd.onion/w/index.php?title=Trust
If this step is not followed, OpenPGP is only secure as TLS. It is often impossible to meet this condition of meeting in person. To mitigate the risk, any OpenPGP fingerprint should be cross-referenced on multiple "secure" ( https:// ) sites. An additional fail-safe is to use an alternative authentication system, for example comparing the Tor signing keys on both the clearnet and .onion domains.