The best way to save and open three.js scene

Now I have this error :

I worked on reducing the userData of all the objects, but when I restore it I get a black screen, and this example for that: test_cors

In the first run, it will store JSON and after 30 seconds it will restore it.
You can see the log.

@Mugen87 How we can do the same thing only not with the whole scene but with an object, mesh, etc., so that we can then add the object to another scene. ?