The '#each' loop cannot be used for many-to-many relationships in a marketing email. I'm trying to access a contact's marketing lists (default entity 'list') to display a text box based on the list id.
Unfortunately, the loop doesn't work with this type of relationship. The code never step into the loop.
it seems it is unsupported at the moment. But it is not documented properly here: https://docs.microsoft.com/en-us/dynamics365/marketing/dynamic-email-content#how-assist-edit-presents-database-relationships
But this is a huge business loss for the customer. Without the workaround, the project would be over. Well-known standard functions would have to be added to the e-mails, otherwise they cannot be used.