Open Inbox as Sidebar

Just an idea I had; the Inbox should be more powerful and more intuitive to use.

On the "Friends" window, there's so much blank space in the area that displays the friends and in the "active now" sidebar that it seems like there should be the ability to have the inbox always open, either split the Active Now sidebar in half so its height is reduced and use the remainder of the screen height for the Inbox (See Option A), or add the Inbox as another sidebar adjacent to the Active Now sidebar (See Option B). I prefer option A, but it seems like either would be a good use of space. Maybe there could even be the option to switch between the two? 🤔