Can't find UIModalPresentationStyle enum value blurOverFullScreen

Question

I am now developing a modal view presented on UINavigationController. I tried to blur the content of UINavigationController's rootViewController under the modal view.

So I set up modalPresentationStyle value as .overFullScreen or .overCurrentContext. But I can't get the right result.(A blurred effect was shown for a second and it was disappeared.)

I read Apple's document and found that there is .blurOverFullScreen configuration on it.

But I can't use it on my environment(Xcode 10.1).

Please help me how I should solve this issue.

Thanks.