Hi, trunk 04-16 has a quite apperant improvment of performance, thunderbird starts up faster than the first prealphy, shows email contents faster, and thank devs. however if you compare ti with those excellent email clients like Becky!, the bat, eudura and so on, there is a long way to go.
1, Automatically expand mailbox when new mail is received in inbox folder, otherwise hide it for saving real estate.
2, Add maxmized view for mail, feature like Becky! full screen view.