How to filter/limit for syntactically invalid From: line?

[Will Yardley]

On Mon, Feb 03, 2025 at 05:53:59PM -0500, Ofer Inbar wrote:
> googly.negotiator862 at aceecat.org wrote:
> > On Mon, Feb 03, 2025 at 09:08:46AM -0500, Ofer Inbar wrote:

> > > From: aaaaa.org" <no-reply at aaaaa.org>
> 
> > The first thing I'd try: ~f'^@$'
> 
> Oh interesting, that does work!  I thought the "@" in the index was
> just a display artifact of some sort, but it looks like mutt really
> does think the from string for these sorts of messages is literally
> "@" so anchoring the regex works.

It would probably be less performant / efficient, but if that didn't
work, or it were harder to know what to filter on, could also look at
using ~h (or =h for IMAP), since that will presumably be looking at any
header field, and might let you do a more literal regex search on the
whole field?.

Other thing to look at might be what the envelope-header (Return-Path
and the UNIX from line, if it exists) and Sender header show up as,
though doesn't seem like there are any simple patterns that make direct
use of either of these.

Maybe there's a reason you're not already, but might also consider
filtering the messages matching this pattern so you don't see them in
the first place.

w