compare:

    * <jon+markdownbug@example.org>
    * <jon.markdownbug@example.org>

* <jon+markdownbug@example.org>
* <jon.markdownbug@example.org>

It seems putting a '+' in there throws it. Maybe it's a markdown bug, or maybe the obfuscation markdown applies to email-links is being caught by the HTML sanitizer.

 -- [[users/Jon]]

> It's a markdown bug. For some reason, markdown doesn't recognize the email with a '+' as an email:
>
>     $ echo '<a+b@c.org>' | markdown
>     <p><a+b@c.org></p>
>
> htmlscrubber then (rightly) removes this unknown tag.
>

>> Filed [in CPAN](http://rt.cpan.org/Ticket/Display.html?id=37909)
>> --[[Joey]] [[!tag done]]

> But I've noticed some other Text::Markdown bugs that, even with htmlscrubber, produce
> [ill-formed (X)HTML](http://validator.w3.org/check?uri=http%3A%2F%2Fikiwiki.info%2Fbugs%2Fmarkdown_bug%3A_email_escaping_and_plus_addresses%2F).
> (View the markdown source of this page.)
>
> --Gabriel

>> The htmlscrubber does not attempt to produce valid html from invalid. It
>> attempts to prevent exploits in html. The tidy plugin can force html to
>> valid. --[[Joey]]

<tt>

- 
>
