Convert Texture2D to PNG

Texture2DUtils.cs

using System.IO;
using UnityEditor;
using UnityEngine;

public static class Texture2DUtils
{
    [MenuItem("Assets/ConvertToPNG")]
    public static void ConvertToPNG()
    {
        var tx2d = Selection.activeObject as Texture2D;
        var bytes = tx2d.EncodeToPNG();
        File.WriteAllBytes(Application.dataPath + "/" + Selection.activeObject.name + ".png", bytes);
        AssetDatabase.Refresh();
    }
}