Gibberish arabic/persian comments in android studio 2.2.3

Question

After installing the new update of android studio 2.2.3, the comments I made in Persian language are turned into gibberish. If I copy them and paste anywhere outside android studio, they will be turned back to their normal form.

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        String string = "من اندروید ستودیو 2.2.3 استفاده میکنم";
        //من اندروید ستودیو 2.2.3 استفاده میکنم
        /*من اندروید ستودیو 2.2.3 استفاده میکنم*/
    }
}

As you see in the image: if I store them as a string variable the text characters are shown correctly but if I comment the same text its characters will turn completely gibberish and obscure.

Can anybody help me resolve this issue? or is this some sort of bug? Thanks.