Plaintext emails do not display
Summary
When I disable sending HTML emails, the emails I get are blank.
Steps to reproduce
Enable "disable HTML mails" in Admin -> Settings -> Email -> "Enable HTML Mails"
Expected behavior
To see the plaintext output
Actual behavior
No output (looking at the email source shows it, some mixup with mime encoding I'm guessing)
I enabled this on 8.15.3 EE and while I get the emails, I have to look at the source to see the actual content I expect to see. I checked with my mail client (MailMate) and with the Gmail client on iOS and the Apple Mail client on iOS.
This was implemented in issue #24880 (closed) but I'm guessing it wasn't tested?