How to find content-id?

Question

HTML

I use the ePochta Mailer mailing service. How to find out the content-id of an image in order to attach it?

Answer 1

As I understand it, the task is not to attach an image, but to insert it Inline into the body of the letter so that it is shown when opened?
To do this, a tag usually helps and attach it to the letter. I didn't check it specifically in ePochta, but it works in many other mailing systems. <img src="cid:НАЗВАНИЕ_ВАШЕГО_ИЗОБРАЖЕНИЯ">