Hello Ossopite,
it is actually the standard to add the device name to the Message ID to assure the ID is indeed unique and other desktop clients should use this standard.
Sender domain is used when you create/send your message through webmail (because it does not have information about your device name).
If you are concerned about your privacy, perhaps change the device name to something neutral.
hello ! i noticed if Message ID [sender domain] - gmail does not put in spam. if if Message ID [computer name] gmail puts in spam the same letter . em-client sets default [computer name] - in the end, the letters go to spam . I wanted to buy your program but there is no option to enable it Message ID [sender domain]. it’s not difficult to create this additional option.