Updated for new board format. This was taken from some other ladies on the board.
If
you go into preferences under signature settings, there is a button on
the editing panel that is a white page with red <>. If you click
that, you should be able to copy and paste the source in there, and then
unclick it and it should come back with what you want.
That goes for source codes popping up instead of pics and tickers as well.