Run HelloFullscreen and press Esc immediately, before the full screen banner disappears. The app crashes:

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0 libsystem_kernel.dylib 0x00007fff965e0212 __pthread_kill + 10
1 libsystem_c.dylib 0x00007fff8cc5aaf4 pthread_kill + 90
2 libsystem_c.dylib 0x00007fff8cc9edce abort + 143
3 libjvm.dylib 0x0000000100f771b3 os::abort(bool) + 25
4 libjvm.dylib 0x000000010109183e VMError::report_and_die() + 2268
5 libjvm.dylib 0x0000000100f78d55 JVM_handle_bsd_signal + 1100
6 libjvm.dylib 0x0000000100f75089 signalHandler(int, __siginfo*, void*) + 47
7 libsystem_c.dylib 0x00007fff8cc478ea _sigtramp + 26
8 libobjc.A.dylib 0x00007fff95a94250 objc_msgSend + 16
9 com.apple.AppKit 0x00007fff8fc0433b -[NSWindow performKeyEquivalent:] + 82
10 com.apple.AppKit 0x00007fff8fc04114 -[NSApplication _handleKeyEquivalent:] + 462
11 com.apple.AppKit 0x00007fff8fac1243 -[NSApplication sendEvent:] + 4480
12 com.apple.AppKit 0x00007fff8f9d72fa -[NSApplication run] + 636
13 libglass.dylib 0x0000000174c597f7 -[GlassApplication runLoop:] + 1783