Is there a way to prevent opening a new browser window when a mailto/email address link in an email is clicked?
The reason why the link clicked in an email redirects to a new browser window occurs is because the link is a tracked link. As per design of Marketo tracked links, they are required to be loaded in a browser first which is why the mailtolink/email address clicked is loading in the browser first.
If you wish to load the link clicked in the same window and not redirect to a new browser window, you will need to disable tracking on the link.
Is this article helpful ?