Drupal 9

Drupal 8 is supported until November 2, 2021. All Drupal 8 sites need to be upgraded to Drupal 9 by then. Drawing from the lessons of hard and painful migration from Drupal 7 to Drupal 8, Drupal devs have decided to make the transition from 8 to 9 as smooth as possible. Reading tweets and blog posts it may seem "it's just the matter of running update.php". Is it though? Here are some things you may want to know.