email from a friend who uses protonmail as their MTA suddenly started to be opportunistically encrypted with pgp; i.e. the sender's MUA did nothing to cause the encryption. i believe this started when i provided my pgp public key over WKD [0]. i have a guess. i suspect that protonmail opportunistically tests for a WKD for the recipient and, if found, uses it. i do see protonmail queries to my WKD service /var/log/httpd-access.log:185.70.40.57 - - [14/Jan/2021:08:44:41 +0000] "HEAD /.well-known/openpgpkey/policy HTTP/1.1" 200 - "-" "GuzzleHttp/6.5.5 curl/7.29.0 PHP/7.4.11" /var/log/httpd-access.log:185.70.40.57 - - [14/Jan/2021:08:44:42 +0000] "GET /.well-known/openpgpkey/hu/pbe8wr5gm5b4gf43adj411yrreqyib6u?l=randy HTTP/1.1" 200 26027 "-" "GuzzleHttp/6.5.5 curl/7.29.0 PHP/7.4.11" /var/log/httpd-access.log:185.70.40.57 - - [14/Jan/2021:10:49:44 +0000] "HEAD /.well-known/openpgpkey/policy HTTP/1.1" 200 - "-" "GuzzleHttp/6.5.5 curl/7.29.0 PHP/7.4.11" /var/log/httpd-access.log:185.70.40.57 - - [14/Jan/2021:10:49:45 +0000] "GET /.well-known/openpgpkey/hu/pbe8wr5gm5b4gf43adj411yrreqyib6u?l=randy HTTP/1.1" 200 26027 "-" "GuzzleHttp/6.5.5 curl/7.29.0 PHP/7.4.11" /var/log/httpd-access.log:185.70.40.57 - - [14/Jan/2021:15:02:49 +0000] "HEAD /.well-known/openpgpkey/policy HTTP/1.1" 200 - "-" "GuzzleHttp/6.5.5 curl/7.29.0 PHP/7.4.11" /var/log/httpd-access.log:185.70.40.57 - - [14/Jan/2021:15:02:49 +0000] "GET /.well-known/openpgpkey/hu/pbe8wr5gm5b4gf43adj411yrreqyib6u?l=randy HTTP/1.1" 200 26027 "-" "GuzzleHttp/6.5.5 curl/7.29.0 PHP/7.4.11" my interest is whether WKD publication is triggering opportunistic encryption; if anything else might be using it opportunistically, and if this can actually scale. i really do not want to discuss if pgp encryption is a good thing, if opportunistic encryption is the spawn of the frog goddess, or if there are viable alternatives to emacs. anyone with protonmail clue or contact(s)? randy [0] - https://git.rg.net/randy/randy/src/master/pgp-WKD.md