// IE11 WeakMap frozen keys fix
// We can't use feature detection because it crash some old IE builds
// https://github.com/zloirock/core-js/issues/485
if (NATIVE_WEAK_MAP && IS_IE11) {
InternalWeakMap = collectionWeak.getConstructor(wrapper, 'WeakMap', true);
// IE11 WeakMap frozen keys fix
// We can't use feature detection because it crash some old IE builds
// https://github.com/zloirock/core-js/issues/485
if (NATIVE_WEAK_MAP && IS_IE11) {
InternalWeakMap = collectionWeak.getConstructor(wrapper, 'WeakMap', true);