❔ Newtonsoft, count nested properties

public static Dictionary<string, int> CountNested(this JObject obj, Dictionary<string, int>? countedProperties = null)
{
    Dictionary<string, int> countedProps = countedProperties ?? new();
    foreach (KeyValuePair<string, JToken> kvp in obj)
    {
        countedProps.IncrementCount(kvp.Key);
        foreach (JObject childJObject in kvp.Value.Children().OfType<JObject>())
        {
            Dictionary<string, int> childResults = CountNested(childJObject);
            foreach (KeyValuePair<string, int> resultKvp in childResults)
            {
                countedProps.IncrementCount(resultKvp.Key, resultKvp.Value);
            }
        }
    }
    return countedProps;
}

private static void IncrementCount(this IDictionary<string, int> dict, string key, int amount = 1)
{
    if (dict.ContainsKey(key))
        dict[key] += amount;
    else
        dict[key] = amount;
}