The Messenger of Allah ﷺ performed the funeral prayer over a deceased person, then came to the grave and threw three handfuls of soil onto it from the side of the head.
حدثنا العباس بن الوليد الدمشقي حدثنا يحيى بن صالح حدثنا سلمة بن كلثوم حدثنا الأوزاعي عن يحيى بن أبي كثير عن أبي سلمة
أن رسول الله ﷺ صلى على جنازة ثم أتى قبر الميت فحثى عليه من قبل رأسه ثلاثا
Sourcing, [its isnad is hasan] Mizzi reported it in Tahzib Kamal, 11/312, in the biography of Salama bin Kulthum, through the hadith of Abbas bin Walid with this wording, adding that he pronounced the takbir over her four times. Ibn Abu Dawud graded it sahih, while Abu Hatim said it was invalid. Ibn Mulaqqin also graded it sahih, h. 821.