Comment 12 for bug 411358

(In reply to comment #6)
> This is a plain text message.
> Even the email from bugzilla (your comment) triggered this bug.

Is the problematic string with ":" linkified by Tb?
Does your problem occur with next setting unchecked?
  Tools/Options/Security, E-mail Scam
  [ ? ] Tell me if the messag I'm reading is a suspected email scam