Yes, Kirby
In 1.5.20 in Template "index.php?account/contact-details" please change the phrase "receive_site_mailings" to the phrase "receive_site_mailings_option"
After that "register" uses "receive_site_mailings" only and "ACP" and "contact-details" uses "receive_site_mailings_option"
=> Register "I accept ....." Actice part
=> ACP / contact-details "This function ...." Passive part