question #3 Sahih al-Bukhari 857, Book 10, Hadith 248 : What role does Ibn `Abbas play in the transmission of hadiths related to funeral prayers?

I heard Ash-Shu`bi saying, “A person who was accompanying the Prophet (ﷺ) passed by a grave that was
separated from the other graves told me that the Prophet (ﷺ) once led the people in the (funeral) prayer
and the people had aligned behind him. I said, “O Aba `Amr! Who told you about it?” He said, “Ibn `Abbas.”