[Coco] OT: Self-modifying email??!!

[Aaron Wolfe]

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On Oct 11, 2013 11:31 PM, "Arthur Flexser" <flexser at fiu.edu> wrote:

> I'm hoping somebody on the list can figure out what is going on here.
>
> A few days ago I received a coupon from Chevy's restaurants, a welcome
> for joining their email discount club.  The coupon was in the body of
> the email itself, and did not require clicking on a link;   you just
> had to print out the email.
>
> I opened it a few times in the next few days, but did not get around
> to attempting to print it until about 10 days after first receiving
> it.  When I opened the message on that occasion, it appeared different
> in an important respect:  The coupon was overlaid with an exclamation
> point surrounded by a triangular border, beneath which was the
> following text:  "Sorry.  This offer has been viewed too many times".
>
> Aside from the question of why the restaurant would choose to cause
> such an overlay message (the coupon still had weeks left until it was
> due to expire), I'm puzzled by HOW they were able to accomplish the
> trick while the message was sitting passively in my Inbox folder.
>
> To make things more puzzling, the overlay disappeared a couple of days
> later, after I complained to Chevy's and they replaced the coupon with
> an additional similar email.  It disappeared not only on my copy of
> the original mailing, but also on another copy of that original that I
> had forwarded to someone.  That person saw the same thing I did:  the
> overlay was visible when he first looked at my forwarded message, but
> was no longer visible when he looked for it later after I asked if he
> could still see it.
>
> If anyone would like to have a look at this unusual message and
> perhaps poke into its html code to see how this trick was
> accomplished, please let me know and I'll forward you a copy.
>
> I wouldn't have thought it possible for the sender of a message to
> affect its content after it had been received by the recipient.  It
> seems rather invasive, somewhat like the sender of a postal letter
> stealing it back from my mailbox temporarily in order to modify its
> content.
>
> Art
>
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