It's easy to miss - I still find myself looking for the reply and forward buttons, and I've been using it a couple of years. (Not daft, just don't reply much... )
Learn the hotkeys. They are quite useful. Forward is "f", reply is "r", compose is "c"... The only one I ever forget is send, which is "tab + enter". I keep trying to "Alt+s" like in outlook.
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