Is it possible to detect whether the customer has opened the email_html/css_WEB-ITnose

html email database HTML email

Reply to discussion (solution)

Works.
Insert an image into html, and the image address is an absolute external address. For example, xxx.com/counter.gif?id=unique identifier (or .php .jsp .aspx .asp) will do. Make sure that the external address first performs query and statistics (that is, based on the id), and then returns a transparent mime type of A 1*1 picture of gif is enough.
Or you can use a linked style sheet, the principle is the same