Contribution pages without additional profiles included create duplicate contacts
Drupal 7, CiviCRM 5.19.4 Authorize paymemt processor Problem is that the Billing address profile seems to be ignored for the dedupe rules. If you use just the default unsupervised rule with name and email and you create the simple contribution without additional profile you will get duplicate contact. You must create a new profile with all fields needed for dedupe rule and include it in contribution page. This requires the user to enter name twice though because the billing address fields pop up. The billing address fields are not used for matching the duplicate although they are used for creating a contact. This is very confusing.