Deletion of a dynamic properties to JSObject ends up using all memory

Whenever a new Geometry object (with its name) is added, a dynamic property is added to the used JSObject and when Geometry object is removed, the corresponding dynamic property is also removed.

when dealing with thousands of objects, the memory consumption is huge (magnitude of GBs)

Attached example reproduces it:

when this little example starts it takes around 600mb of memory and when it destroy (mouse click on window) memory consumption keeps going up and up until it runs out of the memory.

Using it as simple array keeps the memory consumption around 50mb only.