EML files import - unexpected behavior

I developed a basic WF to add some file_metadata read by an eml filter starting with version 4.7.1 of Mayan-Edms. Everything works OK when I load eml files through the web interface. However, when I import the same files using the Watch folder, Mayan-edms recognizes them as plain text files rather than mail messages.

Imported using Mayan_Edms web interface:
Screenshot 2024-06-12 at 18.20.38

Imported using Watch folder:
Screenshot 2024-06-12 at 18.21.06

Have you heard of this unexpected behavior?

Tanks.

Massimo