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From: David Bremner <david@tethera.net>
To: Gregor Zattler <telegraph@gmx.net>, notmuch@notmuchmail.org
Subject: Re: [bug?][notmuch-emacs] X11: renders Headers with face attributes
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Date: Mon, 25 Mar 2019 09:54:02 -0300
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Gregor Zattler <telegraph@gmx.net> writes:

>
> Is this a bug?  Should untrusted senders be allowed to influence
> how headers are displayed?  I don't think so.  For me this case
> should be handled as a homograph attack
> (https://en.wikipedia.org/wiki/IDN_homograph_attack).

I'm not sure about the threat to the user here, but I agree that it
might make sense to normalize the subject at indexing time. 

>
> I do know there is character folding for searches but emacs would
> need to use the reverse for displaying characters and only
> characters which deviate in a way that is recognized as a font
> attribute.

I'm guessing this would be better handled at the notmuch CLI / library
level, where we have access to utf8 conversion facilities e.g. from
glib. It turns out that these kind of problems (related to locales) are
harder than one might expect.