Thunderbird offers the ability to disable displaying the folder pane at View>Layout>Folder Pane, but that is several keystrokes. Two other email clients, eMclient and Mailbird, both allow one-click options to disable that display and that opens up more screen space and also allows the user to focus on the inbox with no distractions. Although the folder pane has useful links, most of them are not needed on a regular basis. Being able to do a one-click display or hide would be welcome to power users, and offer an option for more screen space to everyone. The code is already there; it's just a matter of providing a small icon in upper left (such as a greater-than or less-than icon that, when clicked, toggles the folder pane display. This is low-hanging fruit, a nice feature where 95% of the code already exists. Please give this active consideration. Thank you.