App Hanging on __ulock_wait since 10.12.4

Hi, I'm the lead developer for Komodo IDE, posting here to hopefully get some insights on a hanging issue our users have been having since upgrading to macOS 10.12.4.

We've had a dozen or so users report the hang and had about as many lldb tracebacks shared. Unfortunately the commonality between them is very random from an application POV, but from the OS POV it always hangs on the following bit:

* thread #1: tid = 0x395c66, 0x00007fffc599d31e libsystem_kernel.dylib`__ulock_wait + 10, queue = 'com.apple.main-thread', stop reason = signal SIGSTOP
  * frame #0: 0x00007fffc599d31e libsystem_kernel.dylib`__ulock_wait + 10
    frame #1: 0x00007fffc5a80aff libsystem_platform.dylib`_os_ulock_wait + 25
    frame #2: 0x00007fffc5a803d2 libsystem_platform.dylib`_os_unfair_lock_lock_slow + 130

The traceback leading up to that tends to be different for most backtraces, though InputContext is a common sight (though not consistently present):

* thread #1: tid = 0x395c66, 0x00007fffc599d31e libsystem_kernel.dylib`__ulock_wait + 10, queue = 'com.apple.main-thread', stop reason = signal SIGSTOP
  * frame #0: 0x00007fffc599d31e libsystem_kernel.dylib`__ulock_wait + 10
    frame #1: 0x00007fffc5a80aff libsystem_platform.dylib`_os_ulock_wait + 25
    frame #2: 0x00007fffc5a803d2 libsystem_platform.dylib`_os_unfair_lock_lock_slow + 130
    frame #3: 0x00007fffc4f83169 libobjc.A.dylib`objc_object::sidetable_retain() + 81
    frame #4: 0x00007fffc4f84a8f libobjc.A.dylib`_object_get_associative_reference + 217
    frame #5: 0x00007fffadc8e5f0 AppKit`-[NSView inputContext] + 296
    frame #6: 0x000000010bb47714 XUL`-[ChildView inputContext] + 100
    frame #7: 0x00007fffae5dce5c AppKit`+[NSTextInputContext currentInputContext_withFirstResponderSync:] + 148
    frame #8: 0x00007fffadc0a212 AppKit`-[NSApplication updateWindows] + 96
    frame #9: 0x00007fffae04238f AppKit`__38-[NSApplication setWindowsNeedUpdate:]_block_invoke.2372 + 68

Keep in mind this is just one example of a backtrace, only the snippet I shared first is common between all the ones we've seen. More backtraces are shared on the github ticket here: https://github.com/Komodo/KomodoEdit/issues/2424

Currently Komodo uses the 10.9 SDK, I figure updating to at least 10.11 could work, but it has some significant implications that I'd prefer not to face at this time.

Is anyone able to give me any insights into this issue? Particularly why it started happening in 10.12.4 and was fine before?

By the way I could not find an appropriate category to create this thread in, apologies if I picked the wrong one.

Thank you