For people who don't like the new look, you can go to preferences->Appearance and select 'Vector (Legacy)'. It does require you to login first which is annoying but at least you can easily go back to the old look.
Edit: You can also have it take up the entire width by hitting the button in the bottom right. Doesn't seem to remember the change for me though so hopefully they add that in soon.
Edit: You can also have it take up the entire width by hitting the button in the bottom right. Doesn't seem to remember the change for me though so hopefully they add that in soon.