iFrame - how to load a page the user just came from?
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I have an iFrame on a webpage and on all the other pages I have a button saying "discuss".  When the user clicks on this button it takes them to the iframe page.

I would like to know how to get the iframe to show the page the user just came from?  i.e the page with the discuss button on it.

This is so that eventually users will be able to discuss the page by viewing it in an iframe.

Thanks in advance,
Daniel.