Hi,
so I solved it. As @magic-overflow mentioned, workflow action doesn’t trigger form event in JS. It trigger on_update event in python. But in my case is workflow state changed also after submit, and then on_update event is not triggered. But i found thread where was written that if some fields are changed after submit, there is:
def on_update_after_submit(self):
which is triggered in this case. So If your workflow state is changing also after submit (or any other field - not only workflow state) this event is triggered.
For recapitulation: workflow state will trigger python events:
def on_update(self): # if state is changed before submit
def on_update_after_submit(self): # if state is changed after submit
Thank you all for help!