>>> "ESF" == Eric S Fraga <e.fraga@ucl.ac.uk> writes:

> On Friday, 18 Mar 2022 at 18:56, Uwe Brauer wrote:
>> I just received an email from the auctex list, that looks in my setting
>> as follows

> You might need to show us the full (raw) email to see what is going on?
> Maybe what "C-u g" shows?

It seems the culprit was 

(setq gnus-inhibit-mime-unbuttonizing t)

That was set to nil, no idea why