Hi Anthony,
I found the described feature but its not what it sounds like:
You can change the toolbar in the top of the main window.
just go to preferences->Look (its the second section) -> toolbars
They might be called a litte different. I just translated my german interface.
There you can change the toolbar of the main window.
Just click on the button right next to the text and add or remove actions that you want in your toolbar.
Unfortunately you cannot change the action of the little arrow, right under the date stamp of the email.
Thus you probably need to learn the shortcut ctrl+shift+R if you want to reply from the main window.
ah and I’m really sorry if I dont reply anymore on this thread. Its because I used a 10min mail for my registration. I mean, this is a forum for an email program… There are things more interessting to me.
hopefully i could help you and any other person reading this thread.
Best regards,
Lukas