How to Add Order Comment and also Allow to notify customer via email?

https://www.drupal.org/project/commerce_checkout_order_fields → - might this module help? At least to leave a comment in the checkout flow as customer?

Thanks Anybody, I didn't look into this issue for a while. What I need is to have a way to send message to customer via Email / Log. Not only when checking out. Something like when, customer order something and it's out of stock, damaged item left. I should tell customer.

This one seems to match what I need but there is no release until now -> https://www.drupal.org/sandbox/vensires/3377345 →

I also found a way to do it via Core Comment + Rules / ECA. However, to try to customize Order page in Commerce is not easy. I can only make comment to appear on the right column, never be on left column. Layout Builder doesn't work for me in Order Commerce page. But, that's like a year ago. Something may have changed. Will try it again sometime.

@abx: ✨ Add customer-facing order comments Active is technically addressing what you're requesting here.

Thanks jsacksick, I already tested it a while ago and it works great but I tried not to use patch for basic functionality to prevent any problem if something has changed in core.