http://www.tryton.org/~irclog/2016-04-07.log.html
https://groups.google.com/forum/#!msg/Tryton/Wz73JjGq8VY/iWHop1BKA68J
But I cannot found a solution, both are only say thanks, its working now, but not show a solution.
http://www.tryton.org/posts/new-tryton-release-36.html
https://discuss.tryton.org/t/migration-from-3-4-to-3-6/17
mailto(to=email.get('to'), cc=email.get('cc'),
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