I can confirm something is wonky with MIME handling in 4.83.
I've been logging MIME types in my MIME ACL for years, for reasons which
started out as "let's see what our ratio of HTML to plain text is":
## Decode MIME parts to disk.
warn decode = default
log_message = MIMETYPE part $mime_part_count: $mime_content_type
condition = ${if eq{$mime_content_type}{}{0}{1}}
Prior to 4.83, this logged all MIME parts separately.
With 4.83 it is, more often than not, only logging the first (or
"outer") MIME part.
I've reverted my update (locally compiled into an RPM in a local
repository) to an earlier version while we get this straightened out.
Unfortunately I'm not in a position today to go code mining :-/
Graeme
