[Users] Not displaying HTML email automatically (sometimes)

[Jerry]

On Tue, 16 Aug 2016 13:42:17 +0100, Paul stated:

>On Tue, 16 Aug 2016 08:30:42 -0400
>Jerry <jerry at seibercom.net> wrote: 
>
>> however, the first HTML did
>> display in the older version of claws-mail. All I can figure out is
>> that they changed their sending protocol on the same day I updated.  
>
>Although it does have a broken structure, previously Claws Mail was
>less strict about this, and previously it would have displayed OK.
>These problems have been noted and will be fixed in due course.
>
>with regards
>
>Paul

I was wondering if you happened to know what RFC(s) deal with this? I
want to send as much information as possible to the Postmaster of the
site where the defective emails originate.

-- 
Jerry