The Messenger of Allah ﷺ was seen in the mosque lying on his back with one leg crossed over the other.
قال حدثنا سفيان عن الزهري
رأى رسول الله ﷺ في المسجد مستلقيا واضعا إحدى رجليه على الأخرى
Its isnad is sahih. It was mentioned previously in 16399.