Honestly didn't know about the debug mode, makes it much easier. I agree that measuring should be simple, but to me this seems to be less of a hassle than downloading a third party script that occasionally needs to be updated to work with new tb versions and is less accurate.
It's not complicated at all either, if we consider only the Y axis it's just |Yneck - Yhand|.
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Using this new method, the current record seems to be 2959