Date: Sun, 02 May 2021 16:35:42 -0400
From: Ken Hornstein <kenh@pobox.com>
Message-ID: <20210502203543.4D40CC0B89@pb-smtp1.pobox.com>
| >today, i looked at the newer rfc5322. if i'm reading it correctly, it
| >appears that the term "obs-phrase" (which is produced by "phrase',
| >if i'm using "produced" in the right sense; phrase is produced by
| >display-name), "suddenly" (well, at least since rfc2822, circa 2020)
| >allows unquoted periods.
A little before 2020 ... But yes, when 2822 was being developed it was
decided that periods in display names were so common (though they'd always
been incorrect) that e-mail parsers really had to be able to deal with them.
Back then there were actually very few genuine e-mail addr (or anything
else e-mail related) parsers - e-mail was simply text shown almost verbatim
to the user (with sometimes the ability to hide some of the header fields).
That meant that whatever was generating e-mail could do almost whatever
it liked, as almost nothing (MH aside) ever really ever checked it.
A lot of users with periods in their name (for whatever reason) did
not understand why they were required to put quotes around their name
in e-mail, when others did not. Discrimination! So, mailers allowed
them not to.
Some mailers today avoid the issue by simply always quoting the display
name, regardless of whether it is necessary or not. That is both
technically correct, and the same for everyone.
| And, if we're being pedantic about it, technically no compliant MUA
| should be GENERATING those messages today. So, there's not an easy
| solution.
No compliant MUA should ever have generated unquoted periods in the
display-name of an address. It was never permitted. But it happens,
and is unlikely to ever stop.
kre