I think the feature of hiding the menu bar using the F9 key could use some work. Currently, there isn't any indicator of when the menu bar is hidden, one of our users accidentally hit the F9 key on their keyboard and was asking why his menu disappeared. What I noticed was with the menu bar hidden, the user's email address still shows on the top of the window, essentially the same size the menu bar and the window controls (minimize, maximize, close), so the purpose of hiding is not effective since the email address remains.
I suggest adding a button or an indicator that the menu bars are being hidden, either alongside the email or on the bottom corners. If space is an issue, the menu bar can also be reactive to a mouse hover when it is hidden with the F9 key, out of the way when it's not needed, appearing when the mouse is over it.
