When going to the preferences and creating a new account, the window is stuck in the middle of the screen, without a possibility to move it. This is quite annoying.

This is a screenshot from a 27" monitor. Look where the task list is. You have to take a train to get there. Why not make the left side more flexible, so that it remains under the mailbox list and gradually moves down as you add boxes. Just planting it in the lower left with such a small font makes it almost useless.