I'm currently working on a custom feature for Drupal 8 Commerce 2.x, and I decided along the way that I wanted to update orders with messages. Documentation on this topic was so light that I decided to write my own post about it!
Your custom module will need to have a couple of additional files:
- mymodule.commerce_log_categories.yml
- mymodule.commerce_log_templates.yml
mymodule.commerce_log_categories.yml
Defines our log categories. e.g.