text/html part of email coming through blank

[jacklenox]

Hello @Roguelazer, me again. I've recently upgraded my computer and have set everything up how I used to have it for sending email via muttdown. I'm having a peculiar issue where it just doesn't seem to be working as expected. The email body I'm receiving looks like this (i.e. I essentially receive the email as plain text without any HTML formatting):

...

--===============4829967231339153806==
MIME-Version: 1.0
Content-Type: text/html; charset="utf-8"
Content-Transfer-Encoding: base64

PGgxPlRlc3Q8L2gxPgo8aDI+VGVzdCAyPC9oMj4KPGRpdiBjbGFzcz0ic2lnbmF0dXJlIiBzdHls
ZT0iZm9udC1zaXplOiBzbWFsbCI+PHA+LS0gPGJyIC8+PC9wPjwvZGl2Pg==
--===============4829967231339153806==
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="vwujxq2xnjm7mti2"
Content-Disposition: inline

--vwujxq2xnjm7mti2
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

!m
# Test
## Test 2
--=20

--vwujxq2xnjm7mti2
Content-Type: application/pgp-signature; name="signature.asc"

...

Any help much appreciated. Thank you. 🙏