your doing right make sur the vale does not contain white spaces, use ‘:trimed’ on value and on messages soaces are %20 because we cant send white spaces in url, maybe bubble convert thos automatically or let me fo a search and see if there are any othe way we can do it
‘mailto:to@example.com?cc=cc@example.com&bcc=bcc@example.com&subject=Your%20Subject&body=Your%20Message’