Simplenews newsletter url ?

Hi ! I’m working on a newsletter ( GDPR ), I have a link to set on a scald image, i can display it in the template, the url is correct, but how can I set the link in the body ? I mean, the whole message is displayed with a print render($build);
I can display the url with a print($rgpd_url) but i will appear at the end of the email, not IN the message.
I thought of typing [[[email]]] on the html simplenews, and on the template a str_replace, and switching [[[email]]] with $rgpd_url.
But it’s not working. So I think str_replace on the template is too late, I need to set this where the email is built. (In my opinion.)
Someone here already experienced this problem ? Do you guys have an idea ? Thanks !

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