I saw the Messenger of Allah ﷺ laugh until his molars became visible. The hadith comes with a long narrative about the story of the last person to leave the Hellfire, and it will appear in its proper place.
لقد رأيت رسول الله ﷺ ضحك حتى بدت نواجذه. والحديث بسياق طويل في قصة آخر أهل النار خروجا منها ويأتي في موضعه.
Bukhari narrated it in Riqaq (6571) and Muslim in Iman (308:186), both from Uthman bin Abu Shayba, from Jareer, from Mansur, from Ibrahim, from Ubayda, from Abdullah bin Masud, who said, and then he mentioned it.