He used to pray on his mount and perform the witr prayer on it, and he would relate this practice from the Prophet ﷺ.
حدثنا يحيى عن ابن عجلان حدثني نافع
أنه كان يصلي على راحلته ويوتر عليها ويذكر ذلك عن النبي ﷺ
Its isnad is sahih. Ibn Ajlan is Muhammad. The meaning of this hadith has already appeared in scattered form at 4470, 4476, 4519, 4530.