We've been trying to use CircularBuffer as the basis of a weighted circular buffer, using shift / pop to bring the total size back down if increased beyond a threshold by push / unshift, however we noticed the memory of items in the buffer is still retained after the shift / pop.

This seems to be because the fixed-deque impl of those methods is just shifting the pointers and returning the element, and never deleteing the index in the array, preventing the items from being GC'd