Re: [ietf-822] folded URLs

["John R Levine" <[e-mail]>]

>> So in that case, would a reasonable update to RFC 2369 be to impose a
>> character limit of 998 characters on list header fields, including the
>> List-Unsubscribe header field? ...

> Now, if there was evidence that people are attempting to put huge
> URLs in List-* headers and causing problems then there would be justification
> for adding some text about it. But IMO it would still not rise to the level
> of calling for an update to the specification.

The question that started this was an observation that some software does 
a poor job of unfolding folded URLs in headers.  That's clearly a quality 
of implementation issue, like a lot of other issues in mail, and there is 
no reason to believe that waving fingers at people who misimplement stuff 
will make any difference. It's hardly the only place that unfolding URLs 
doesn't work -- try copying and pasting a URL that some MUA helpfully 
folded while quoting a message in a reply.

I suppose it would be nice to have some place to put advice like your life 
will be easier if your URLs fit on one line, but standards track RFCs 
doesn't seem like it.

Regards,
John Levine, [e-mail], Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly

PS to Peter: in case it's not obvious, I do appreciate your finding places 
where the ABNF disagrees with the practice, even if we don't always agree 
on what to do about it.