Game window can no longer be resized after exiting fullscreen

Steps to reproduce:

• In Launcher select profile for 1.8.2-pre5 or 1.8.2-pre6
• Start the game in fullscreen or enter fullscreen by F11
• Exit fullscreen by F11
• Game window cannot be resized

The game window has a thin border (compared to 1.8.2-pre4) and the maximize button is greyed out.

Possibly a LWJGL issue since this effect happens since 1.8.2-pre5