Just been looking at Thunderbird and it looks pretty good… but! and it’s a big BUT, there should be native translation of emails to the language you require, this would be a game changer for Thunderbird, being able to read a Portuguese email in English and then replying in English and the recipient would receive the email in Portuguese, if you get what I mean.
As it stands, the addons aren’t good enough and I need a feature like this (atm I’m reading translated emails in Chrome on Gmail, then use Google translate to reply, copy,n,paste) with Thunderbird I have to copy,n,paste just to read an email, let-alone replying. so it’s to much hassle using Thunderbird for me.