Python objects "leak" when passed to Javascript

[mdboom]

Since there is no concept of a finalizer in Javascript, there is no way to decrement the Python object's reference count when it goes out of Javascript scope or is collected by the gc.

One solution is to add such a feature to Javascript (lol).

Another might be to pass weak references to Javascript and just let Python deal with lifetimes alone, and accessing a dead object from Javascript would raise an exception.

[mdboom]

This is mostly addressed by the new feature to explicitly destroy Python objects from Javascript.