Is there any easy way to determine if the html loaded into the editor text box has been changed?

 

For example is there some call that would return the length of the undo stack?

 

We would like to alert the end user if changes are about to be lost (due to failure to save the changes to a page.).

 

I suppose it would be possible to hold the original source in a session variable, and then compare current editor html to the saved starting point.  I am however concerned that Cute editor may alter input source for it's own  purposes during load.

Also not very pleased with the performance impact of very large session variables.