On 8/26/23 21:33, Theodore Ts'o wrote:
On Sat, Aug 26, 2023 at 01:09:03AM -0400, Keith Moore wrote:
For a good time, take a look at schema.org which has a whole bunch of
sets of tagged HTML elements you can embed in messages and that a lot
of large mail systems will interpret as things ranging from drug
formulas to concert tickets. The SML WG is looking at standardizing it.
So what? We don't have to change the meaning of HTML that people are
already using in email, in order to define a subset/profile of email for use
in technical discussions (or however else we want to scope it)
The challenge is how do you *enforce* that e-mails conform to this
subset/profile of HTML?
If, say, a list, or a recipient, wants to enforce a subset or profile,
it can do so by implementing a filter that removes elements that don't
conform to the profile.
A list can, if it wishes, also bounce email that doesn't conform to the
profile, or that egregiously fails to conform to the profile.
If tools to do these things become widely available and become widely
used by mailing lists, there will be pressure on MUA vendors/authors to
implement that subset.
It's also possible that some mailing lists will develop reputations of
enforcing that subset, and that MUAs will learn which lists enforce that
subset and avoid sending noncomformant HTML to those lists.
But what you are proposing is not requiring plain text, but some
artificial HTML subset/profile.
Well, sure. Every new protocol is "artificial" until the details are
settled on.
Also, this presumably isn't an arbitrary variant of HTML - it's
presumably a variant that can display and operate correctly on existing
web browsers and MUAs that implement HTML. And presumably the set of
elements disallowed won't be arbitrary, but will be those that fail to
meet some agreed-on criteria that are found to be reasonable for email.
And that might actually be a lot
harder compared with sending plain text --- which some people seem to
claim is Impossible(tm). (Which is fine, just don't bother the Linux
kernel which is doing it when you try to claim that it's Not Possible. :-)
It's not that hard to force MUA's to send plain text. But forcing
MUA's to send an IETF custom HTML subset may be quite a bit more
difficult.
I certainly don't believe it's impossible to restrict list traffic to
plain text. If that's what IETF Consensus wants, I'm okay with it. I
think there are some potential benefits to allowing some XML-like
structure in list messages, and I lean at least slightly toward that
kind of solution. But that's not the only way to address the problems
IETF is having with email, and I also recognize that there are potential
benefits to extreme simplicity.
Keith
