I saw Abu Hurayrah prostrate during the recitation of "When the sky is split asunder" [Inshiqaq 84:1], so I said to him, "You prostrated in a surah where prostration is not customary?"He replied, "I saw the Messenger of Allah ﷺ prostrate in it."
حدثنا يزيد قال أخبرنا محمد بن عمرو
رأيت أبا هريرة سجد في إذا السماء انشقت فقلت سجدت في سورة ما يسجد فيها قال إني رأيت رسول الله ﷺ يسجد فيها
Its chain is sahih. Abu Salama is Ibn Abdul-Rahman bin Awf, mentioned many times before. The hadith is found in all Six Books except Tirmidhi. Muslim narrated it in the Book of Mosques, chapter on sujud during recitation, 1/406, no. 578. Abu Dawud narrated it in 2/59, no. 1407, in the Book of Prayer, chapter on sujud during Inshiqaq. Nasai narrated it in the Book of Opening the Prayer, 2/161, no. 961, chapter on sujud during Inshiqaq. And Malik narrated it in the Book of the Quran, chapter on what has been said about sujud of the Quran, 1/205.