title: How to dock Objects Library in Xcode 10
body: <p>After I upgraded to Xcode 10. I noticed that the Objects Library is floating instead of docked at right bottom corner.
  And a new button added at the top tools bar.
  How can I dock it to the corner as Xcode 9 did.
  <a href="https://i.stack.imgur.com/TW9Ph.png" rel="noreferrer"><img src="https://i.stack.imgur.com/TW9Ph.png" alt="enter image description here"></a></p>