Drupal: How to get node id on hook_page_build(&$page)? (3 Solutions!!)

Drupal: How to get node id on hook_page_build(&$page)? Helpful? Please support me on Patreon: https://www.patreon.com/roelvandepaar With thanks & praise to God, and with thanks to the many people who have made this project possible! | Content (except music & images) licensed under CC BY-SA https://meta.stackexchange.com/help/licensing | Music: https://www.bensound.com/licensing | Images: https://stocksnap.io/license & others | With thanks to user mohit_rocks (drupal.stackexchange.com/users/1022), user John (drupal.stackexchange.com/users/1997), user Gabor Szanto (drupal.stackexchange.com/users/10312), user Anoop Joseph (drupal.stackexchange.com/users/10405), and the Stack Exchange Network (drupal.stackexchange.com/questions/48706). Trademarks are property of their respective owners. Disclaimer: All information is provided "AS IS" without warranty of any kind. You are responsible for your own actions. Please contact me if anything is amiss at Roel D.OT VandePaar A.T gmail.com