She said that whenever the muadhin finished the call to prayer for the dawn prayer, the Messenger of Allah ﷺ would pray two brief rakahs before the prayer was called to begin.
قالت إن رسول الله ﷺ كان إذا سكت المؤذن عن الأذان لصلاة الصبح صلى ركعتين خفيفتين قبل أن تقام الصلاة.
Malik narrated it in Salat al-Layl (29) from Nafi, from Abdullah bin Umar, from Hafsa, and he related it as I have mentioned. Bukhari narrated it in Adhan (618) from Abdullah bin Yusuf, and Muslim narrated it in Musafirin (718) from Yahya bin Yahya, both of them from Malik with this wording, except that Bukhari said in the wording of the hadith, "The Messenger of Allah ﷺ, when the mudhin had settled into itikaf for the dawn prayer and dawn had begun, would pray two light rakahs before the prayer was called to stand."His statement "had settled into itikaf" has puzzled many scholars, who offered unconvincing explanations for it. Ibn Hajar concluded that it was most likely a corruption of the word "fell silent."