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No content encoding in email headers

Hi there.

We have an application running passwordless authentication. For a number of reasons, our emails are often being left as spam in customer’s mailboxes. After contact with an email provider they agreed to give us a list of rspamd rules our messages had breached, one of the most significant, R_MISSING_CHARSET is triggered when an encoding isn’t specified in the content-type header.
Just to be completely sure, is it Auth0 that crafts these headers when it sends the mail? And if so, could you add this to the headers?

You can see the rules here. https://github.com/rspamd/rspamd/blob/373090429416571046f333c1f68707bb752e562d/rules/regexp/headers.lua#L140-L147

While the rule appears to be only affecting text/plain segments, I’ve noticed previous versions match all text types, so it may be best if all segments set character encoding. From what I’ve seen the meta tag that is set in the default email template html won’t be read.

Hey there @joe.whittles!

Can you tell me what email service provider you use?

We’re using Mailgun over the SMTP provider.

Thank you for providing that context. Unfortunately I don’t have experience with Mailgun but let me discuss it with the team and get back to you!

1 Like

Hi there Konrad. Any update?

Hey there Joe!

The team is still researching that. Could you send me your tenant name via private message and also a sample of one raw email message with headers?