I've upgraded my store to 3.1 and fixed my custom foxybox.css to work with the new version of Thickbox (which I like BTW). The only thing I can't figure out is how to remove the left-double-arrows << or "«" from the continue shopping button. Any help is greatly appreciated.
If you want to see an example of what I'm talking about go to:
and click on the "Add to Cart" button. The resulting foxybox shows the unwanted arrows on the "Continue Shopping" button.