Hi, >> I see that mumi fails to render https://issues.guix.gnu.org/issue/37444. > > This is due to an invalid charset in the Content-Type header of message > 107 (debbugs numbering). In the event of such invalid Content-Type > headers, RFC2045 recommends assuming the default Content-Type header. I > have now implemented this recommendation in > guile-email. See commit https://git.systemreboot.net/guile-email/commit/?id=6159257c9da3664c516a26fad1ee942068fbbdd2 > > Could you try again with this latest fix and let me know if it works? Just a friendly ping. Did this work for you?