Merge anonymous contacts on email link

Your software
My Mautic version is: 4.3.1
My PHP version is: 7.4.29
My Database type and version is: 10.5.10-MariaDB

I have created a number of contacts with emails through the API. I also have anonymous users showing up from page hits on my website. I expect that when I send an email to a known user for the first time and they click on an email link it will merge their existing anonymous user’s history into the known contact.

As of right now when the user clicks an email link the anonymous user and its history is abandoned, with new events being tracked on the known user.

Is this a configuration issue or is this behavior not supported by Mautic?

Mautic merges data with the known user first and if it’s not available, then with anonymous user.
If you create a user with an API, then it’s a known user. Anonymous visits will not be merged.

Here is a thread discussing exactly this: