It`s a nice suggestion. I would recommend shift+del though since it`s more standard for permanent delete, at least in Windows.

I think I could parse the query strings when the page loads and then post them to the iframe, or maybe append the strings to the iframe url and create it dynamically.

Now I noticed that the iframe workaround brings a new problem, I can't request fullscreen anymore. Any ideas about how to solve this?

superkew

Try to design your levels using modular parts that can be re-used and combined to construct the scene. By using instances instead of new objects the memory usage can be significantly reduced.

You can also upscale low detail images in the editor (like background gradients) to fill a big area without compromising memory usage or quality. The key is to find the balance between re-usability and variation.