email-print-mime-structure: use only BOX DRAWINGS

[Sean Whitton]

Hello,

On Wed 16 Jul 2025 at 06:05pm -04, Daniel Kahn Gillmor wrote:

> Hi!  This brief series proposes to change the output of
> email-print-mime-structure to use only the BOX DRAWINGS characters
> from unicode, rather than using more unusual characters.
>
> I've been using these MIME diagrams for Internet Drafts within the
> IETF, and they're struggling with their PDF output, which is
> constrained to a more limited set of glyphs due to a minimal set of
> permitted fonts which themselves only have limited coverage of symbols
> in a fixed-width font.  In particular, this is motivated by the
> discussion at https://github.com/ietf-tools/xml2rfc/issues/1245

Thanks dkg, applied these to my tree.

-- 
Sean Whitton