This is not true.  The same thing is happening to me, but I notice other emails I receive in the same email program don't have this issue. Even with really short preheader text.  I've been messing with this for over an hour .. tried putting an image at the top of the email to block it, but it still finds the first line of my email and appends it to the end of the preheader text. Adding spaces does not work either, even if you put a character at the end of the spaces.  The spaces simply get cut out. Like the OP mentioned, very undesirable!! ... View more