Sometimes clicking the "Show or hide panels" (the top-right icon on right pane for Tools or Comments) in Adobe Acrobat Pro XI v.11.0.2 on OS X 10.8.3 does no work. Clicking it does nothing. Here is the fix:
1. Select View > Read Mode.
2. Select View > Full Screen Mode
3. Press the Escape key
[kirkmc adds: I donít have Acrobat Pro, so I canít test this.]
Mac OS X Hints