How to force web-browser to navigate to Gmail and create (if logged in) new letter with filled in field \'To\' on click on mailto:SomeMail@blabla.com?
To add Subject, Body, CC, and BCC, just add the parameters to the URL:
Example:
https://mail.google.com/mail/?view=cm&fs=1&to=someone@example.com&cc=someone@ola.com&bcc=someone.else@example.com&su=SUBJECT&body=BODY
Or:
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