Bug Can't type in the "Add Behaviour" box in Animator layers

To reproduce:

1. Open the Animator window (Window/Animator)
2. Select an Animator Controller
3. Locate and click on the "Layers" button in the top left of the Animator window, and click on a layer. Notice the "Add Behaviour" button in the inspector.
4. Click on "Add Behaviour". Notice you can't type. (Pressing the Q/W/E/R/T keys changes the scene object interaction mode (move, rotate, scale, etc.))