how to make a form field be required with hook form alter I want to alter a form to make the revision log be required.
with drupal 8, I am adding this in a module 

$form['revision_information']['#required'] = TRUE;


but the field does not become required.  What am I missing?
this was the answer:

$form ['revision_log']['widget'][0]['value']['#required']=TRUE;


thanks for the tip about the widget Kevin