"No one informed that they saw Messenger of Allah praying Ad-Duha except Umm Hani. She narrated that Messenger of Allah entered her house on the Day of the Conquest of Makkah. He performed Ghusl and performed eight voluntary Rak'ah such that she had not ever seen him pray any Salat lighter than them, but that he completed the bowing and prostrations." (Using translation from Tirmidhī 474)
أَنَّهُ رَأَى النَّبِيَّ ﷺ يُصَلِّي الضُّحَى غَيْرَ أُمِّ هَانِئٍ فَإِنَّهَا حَدَّثَتْ أَنَّ النَّبِيَّ ﷺ دَخَلَ بَيْتَهَا يَوْمَ فَتْحِ مَكَّةَ فَاغْتَسَلَ وَصَلَّى ثَمَانِيَ رَكَعَاتٍ مَا رَأَتْهُ صَلَّى صَلَاةً قَطُّ أَخَفَّ مِنْهَا غَيْرَ أَنَّهُ كَانَ يُتِمُّ الرُّكُوعَ وَالسُّجُودَ