Since the update 2 weeks ago, you can no longer use the cursor keys to navigate through objects nested inside the StarterGui class. Using the cursor keys while inside the class simply bypasses though into the game window (Moving the camera in studio/server view and moving the player/rotating the camera in client view).
Clicking on an already selected object inside StarterGui allows for a single navigation via cursor keys before becoming bugged again.
This bug applies in studio view, F5 client view, F7 client view and F7 server view. This bug does not apply to F5 server view.
Cursor key navigation remains unchanged for the other classes.
Normal Navigation
https://gyazo.com/939a1c5a080b16a989e43482a75aec01
Navigation Inside StarterGui
https://gyazo.com/1126b7268e2fd27243d8d9b4350edde1
First input is recognised as StarterGui was already selected, but then future inputs are bypassed through to the camera.