I've just discovered this 'new' project by Phil Zimmerman, Ladar Levison and others.
Its called the 'Dark Mail Technical Alliance'
Its not a competing company to Runbox but a technical alliance.
http://darkmail.info/home.html
I'm aware that none of the elements that they are proposing is covered by any existing RFC standard, their trying to create the next generation of email.
It would be good if Geir and the rest of the Runbox team could give serious consideration to if this consortium is something that Runbox could join.
I think that time invested in this would be better spent than spending resources trying to implement PGP and 2FA support, or doing webmail re-skins.
The Dec 2014 specifications pdf makes for some interesting reading.
https://darkmail.info/downloads/dark...ember-2014.pdf
+ adding link to news article, where comments are mainly along the lines of how the choice of name has negative connotations;
https://news.ycombinator.com/item?id=8822515