How to stop smiley in Thunderbird showing up as a J?

In Thunderbird 3, when I receive a message with a smiley using the "Original HTML" or "Simplified HTML" viewing option, it appears like this:

That is … J. However, if I view the message as "Plain text" I get the smiley

The actual message in the "view source" looks like this:

Content-Type: multipart/alternative;
    boundary="_000_7EE28"
MIME-Version: 1.0

--_000_7EE28
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

Se        r=F3n... :)

That =F3 is an "ó" (I've censored the message for the easily offended Spanish readers out there). Maybe it is something to do with the encoding? I'm on Linux and use LANG=en_US.UTF-8.

Anyone know what has gone wrong here and how to fix it?

EDIT: I've tried switching encoding to ISO-8859-1 and forcing this, but no joy.

After further investigation, it seems that the Wingdings thing is the issue. The actual HTML has the following snippet where the smiley should be:

<span style='font-= size:11.0pt; font-family:Wingdings'>J</span>

... since this is a multipart text/HTML message and I had only added the plaintext part above.

Solution 1:

This Lifehacker article has some explanation on what's going on. What it basically says is that when the sender types in a ":)" character, their Outlook automatically converts it into a smiley rendered in the Wingdings font. As far as I know, this happens when Outlook uses Word to edit email messages.

At the moment, I'm on a box with Outlook installed, not Thunderbird. Is it possible for you to change the encoding to ISO-8859-1 to see what happens?

Solution 2:

Here's my solution. I wrote a Thunderbird Add-on that replaces J, L, è, à, and · with the correct UTF-8 emoticon, arrow or whatever.

Before:

After:

Credit to Isxek for getting me on the right track though!

Solution 3:

A receiver-side solution to this problem would be to install the SWEC (Symbola-based Wingdings Emoticons Compatibility) font: https://drive.google.com/open?id=0BwDrnPQfa-aMOEx0bEZCQUNrSGs

It provides basic compatibility with Wingdings emoticons. (In Wingdings, "J" represents a smile, "K" represents a lack of expression, and "L" represents a frown.) Background: certain versions of Microsoft e-mail clients still in use change user-typed expressions such as ":)", ":|", and ":(" into "J", "K", and "L", respectively, and then specify Wingdings as the font family; recipients on systems which do not include a Wingdings-compatible font are not able to see the intended emoticons, which can cause confusion.