i had the same issue using LWJGL 2.
I decided to give LWJGL 3 a try on El Capitan ("HelloWorld") and ran into an even bigger problem where the app would not even run throwing a bunch of NSException objects (output below).
Hello LWJGL 3.0.0b build 54!
2015-10-31 19:55:31.746 java[604:16692] *** Assertion failure in +[NSUndoManager _endTopLevelGroupings], /Library/Caches/com.apple.xbs/Sources/Foundation/Foundation-1255.1/Misc.subproj/NSUndoManager.m:359
2015-10-31 19:55:31.747 java[604:16692] +[NSUndoManager(NSInternal) _endTopLevelGroupings] is only safe to invoke on the main thread.
2015-10-31 19:55:31.747 java[604:16692] (
0 CoreFoundation 0x00007fff9255fe32 __exceptionPreprocess + 178
1 libobjc.A.dylib 0x00007fff8c2fa4fa objc_exception_throw + 48
2 CoreFoundation 0x00007fff92564b0a +[NSException raise:format:arguments:] + 106
3 Foundation 0x00007fff9126ae16 -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 198
4 Foundation 0x00007fff911eff31 +[NSUndoManager(NSPrivate) _endTopLevelGroupings] + 170
5 AppKit 0x00007fff9484adca -[NSApplication run] + 844
6 libglfw.dylib 0x00000001286267ae initializeAppKit + 1342
7 libglfw.dylib 0x0000000128625ec2 _glfwPlatformCreateWindow + 34
8 libglfw.dylib 0x00000001286227f1 glfwCreateWindow + 513
9 ??? 0x000000011139e954 0x0 + 4583975252
)
2015-10-31 19:55:31.747 java[604:16692] *** Assertion failure in +[NSUndoManager _endTopLevelGroupings], /Library/Caches/com.apple.xbs/Sources/Foundation/Foundation-1255.1/Misc.subproj/NSUndoManager.m:359
2015-10-31 19:55:31.748 java[604:16692] An uncaught exception was raised
2015-10-31 19:55:31.748 java[604:16692] +[NSUndoManager(NSInternal) _endTopLevelGroupings] is only safe to invoke on the main thread.
2015-10-31 19:55:31.748 java[604:16692] (
0 CoreFoundation 0x00007fff9255fe32 __exceptionPreprocess + 178
1 libobjc.A.dylib 0x00007fff8c2fa4fa objc_exception_throw + 48
2 CoreFoundation 0x00007fff92564b0a +[NSException raise:format:arguments:] + 106
3 Foundation 0x00007fff9126ae16 -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 198
4 Foundation 0x00007fff911eff31 +[NSUndoManager(NSPrivate) _endTopLevelGroupings] + 170
5 AppKit 0x00007fff9484ae66 -[NSApplication run] + 1000
6 libglfw.dylib 0x00000001286267ae initializeAppKit + 1342
7 libglfw.dylib 0x0000000128625ec2 _glfwPlatformCreateWindow + 34
8 libglfw.dylib 0x00000001286227f1 glfwCreateWindow + 513
9 ??? 0x000000011139e954 0x0 + 4583975252
)
2015-10-31 19:55:31.748 java[604:16692] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '+[NSUndoManager(NSInternal) _endTopLevelGroupings] is only safe to invoke on the main thread.'
*** First throw call stack:
(
0 CoreFoundation 0x00007fff9255fe32 __exceptionPreprocess + 178
1 libobjc.A.dylib 0x00007fff8c2fa4fa objc_exception_throw + 48
2 CoreFoundation 0x00007fff92564b0a +[NSException raise:format:arguments:] + 106
3 Foundation 0x00007fff9126ae16 -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 198
4 Foundation 0x00007fff911eff31 +[NSUndoManager(NSPrivate) _endTopLevelGroupings] + 170
5 AppKit 0x00007fff9484ae66 -[NSApplication run] + 1000
6 libglfw.dylib 0x00000001286267ae initializeAppKit + 1342
7 libglfw.dylib 0x0000000128625ec2 _glfwPlatformCreateWindow + 34
8 libglfw.dylib 0x00000001286227f1 glfwCreateWindow + 513
9 ??? 0x000000011139e954 0x0 + 4583975252
)
libc++abi.dylib: terminating with uncaught exception of type NSException
My question is, will a patch be made for LWJGL '2' in order to future proof it for just a little bit longer?