Undefined update calls slows down performance

Hi, maybe someone can help me with this:
How can I get where updates-> undefined comes from or what it means?
I get this only with production build (angular cli/webpack) but i can’t find what causing it.
Phaser CE 2.11.1.
Thanks in advance!

Not sure. Try your browser’s JS profiler instead.

Late answer, but may be useful: it was caused by buildOptimizer from Angular cli build (i have a Phaser game as Angular module).