UTF-8 Diacritics interpreted incorrectly

Using Postie 1.9.80 and WordPress 7.1.

My source email has characters with diacritics (Cristóbal) that get mistranslated when they finally wind up in a post (Cristóbal).

The source email is encoded as UTF-8:

Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: base64

The Base64 payload decodes correctly to text containing:

Cristóbal Aguilar
de León

The UTF-8 bytes for ó are correctly present as C3 B3 in the decoded message.

However, after Postie 1.9.80 processes the email, the resulting WordPress post contains:

Cristóbal Aguilar
de León

Postie’s Test Config reports:

default_charset: utf-8
DB_CHARSET: utf8
DB_COLLATE: utf8_general_ci
WordPress encoding: UTF-8

The email is plain text rather than HTML, and the corruption occurs in the resulting post content itself.

I have the complete raw email available, including the MIME headers and Base64 payload, and can provide it if useful.

Can this please be investigated? As an L.A.-based news outlet, we deal with a lot of names that contain diacritics, and this is making us look bad.

Thanks!

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