Hello, I would like to add an observation tangential to your points A), explanation to new contributors, and B) potentially advise against the use of Proton Mail for Debian work to yield a «no, Proton Mail can be useful for some Debian work».
In December 2022/January 2023, I found a sponsor for my first contribution `ruby-mdl`/`markdownlint` (a syntax checker[1]) via mentors.debian.net. In preparation of an upgrade in October 2023, the earlier workflow did not work any more because messages as for instance «your upload was accepted to mentors» did not reach me. The credit is due to Baptiste Beauplat to figure out yahoo no longer accepts the emails by mentors.debian.net which are sent by a hostname.[2] It was (I speculate: possibly still is) uncertain if/when yahoo is going to adjust its policy in favor of Debian. Meanwhile, the free protonmail account provided a bypass to submit again updates of my package to mentors.debian.net .and. to receive again the notifications from this site. For this, I created locally a new GPG key pair about the protonmail address of which the public key was uploaded to salsa.debian.net and mentors.debian.net. This local key pair equally is the one currently used for `debsign` on the .changes file prior to `dput mentors ...changes` to eventually file a RFS on mentors. The local GPG key pair is a different one of the one provided by protonmail, the two already discernible by their different fingerprints. In terms of technology, protonmail's key lists as key type `ECC (Curve25519)` while the options in the Kleopatra GUI[3] offer RSA, DSA, and type ECDSA/EdDSA, too. So in short: for this less than DM-level contribution to Debian, protonmail can be useful. Norwid P.S.: In the longer run, the absence of IMAP/SMTP, the constraint of three folders to organize emails in a hierarchic approach (or three tags to label the messages irrespective a hierarchy) in the free version are incentives to opt-in in pm's subscription based use. [1] https://tracker.debian.org/pkg/ruby-mdl [2] https://wordtothewise.com/2023/05/unresolvable-rfc-5321-domain-at-yahoo/ [3] https://tracker.debian.org/pkg/kleopatra
