Retrieving WYSIWYG Editor content after pressing the back button

Hi,
After reading the devarticles tutorial on creating a WYSIWYG editor, I decided to create one. One problem I've run into, however, is after the "News Post" form is submitted, I have a preview screen where the user can see what the page will look like. If the user wants to edit the post and presses the back button to do so, all the content in the iFrame is gone (unlike a regular textarea, where the content would still be there).

I've read through all the posts that are returned by searching for "WYSIWYG HTML editor" (or any variant thereof), and I'm still confused about this problem.

I did find one post that described this situation, but I just couldn't understand the explanation: URL

So my question is simply this: how can I retrieve the iFrame content when the browser's back button is pressed?

Any help is greatly appreciated!

LS