Got unknown Content-Type: multipart/alternative

https://github.com/mailgun/wordpress-plugin/blob/095851a7e2419f58ac67bb3f5b0a0268671a9765/includes/wp-mail-api.php#L316

Can the code producing an error log on the line above be removed, assuming it is handled with the code that was added – or at least add a new?else if ('multipart/alternative' === $content_type)?option on line 314?

With this in place, logs are filling up with output such as below:

[mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative [mailgun] Got unknown Content-Type: multipart/alternative

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