How to correct Tab Bar height issue on iPhone X

On iOS 12.1 I’ve solved this issue by overriding safeAreaInsets in the UITabBar subclass:

class TabBar: UITabBar {
    private var cachedSafeAreaInsets = UIEdgeInsets.zero

    override var safeAreaInsets: UIEdgeInsets {
        let insets = super.safeAreaInsets
    
        if insets.bottom < bounds.height {
            cachedSafeAreaInsets = insets
        }
    
        return cachedSafeAreaInsets
    }
}

For iOS 13.0 onward,

class TabBar: UITabBar {
    private var cachedSafeAreaInsets = UIEdgeInsets.zero

    let keyWindow = UIApplication.shared.connectedScenes
        .filter { $0.activationState == .foregroundActive }
        .compactMap { $0 as? UIWindowScene }
        .first?.windows
        .filter { $0.isKeyWindow }
        .first
    
    override var safeAreaInsets: UIEdgeInsets {
        if let insets = keyWindow?.safeAreaInsets {
            if insets.bottom < bounds.height {
                cachedSafeAreaInsets = insets
            }
        }
        return cachedSafeAreaInsets
    }
}