UnityEditor.EditorUtility.UnloadUnusedAssetsImmediateInternal C# (CSharp) Method

        private static extern void UnloadUnusedAssetsImmediateInternal(bool includeMonoReferencesAsRoots);
        [MethodImpl(MethodImplOptions.InternalCall)]

 public static void UnloadUnusedAssetsImmediate()
 {
     EditorUtility.UnloadUnusedAssetsImmediateInternal(true);
 }