Known issues
Encoding error in Apple Mail App
ID:
Backlog
Published on 6/26/2018
•
Last update on 12/22/2022
Summary
Apple Mail APP has a bug in the email subject encoding when it has a special character. The subject contains =?UTF-8?Q?S at its beginning.
Apple community link: https://discussions.apple.com/thread/2811597?tstart=0
Simulation
Mount an email sending trigger that has a special character in the "Subject" of the email.
Result:

Workaround
Do not use special characters in e-mail subjects.