Does Postmark support UTF-8 characters in the FROM name?
We do not support UTF-8 characters in email addresses/headers over SMTP. This functionality was added with SMTPUTF8, which is a relatively modern extension to SMTP, but our Postfix servers do not have SMTPUTF8 enabled. There are also some other limitations in our pipeline that need to be updated to support this.
Jira: https://postmark.atlassian.net/browse/PM-3542
Related case: https://secure.helpscout.net/conversation/2117061857/579883?folderId=3975551
Basecamp: https://3.basecamp.com/3093822/buckets/3323243/messages/5706521502