PHP 8 causes emails to arrive showing HTML source

[kb6673]

Hi, I've noticed this on a few sites recently, if we upgrade to PHP 8, the emails are received as HTML code, rather than HTML format.

Rolling back to PHP 7.4 immediately resolves the issue

Various WP versions.
Various Post-SMTP versions too.

The current one I noticed is WP 5.8 & Post-SMTP 2.0.23 (with emails coming from Gravity Forms)

[kb6673]

Still getting this in PHP 8.1

Anybody else having a similar issue?

[lorenzofaresin]

+1 Me too WP 6.0 & Post-SMTP 2.1.7 (with emails coming from Gravity Forms + Post SMTP test email)

[smusmanobjects]

Hi,

I hope you're doing well, apology for late response.
This is beta, using this will resolve the issue: https://github.com/wpexpertsio/Post-SMTP/archive/refs/heads/dev.zip

Thanks