Sorry but I think the iframe is a very bad practice:
1- Lose the interaction with the site.
2- Consume the same memory, and for user waiting 5 or 10 minutes for browser decide to empty the memory is horrible.
3- We need interaction Normal Web With the C2 for a better designs or web aplications
I have a magic temporary solution :P (C2 MAGIC).
When finish the game I go to a clear layout with black background and On start of layout execute the javascript fuction to remove, and the C2 consumition are reduced to a minimun.
Thanks guys for the intension to help me.
Sorry for my english.
Greetings.-