What did the Messenger of Allah (peace and blessings be upon him) do specifically during the last ten days of Ramadan?

Question : The Messenger (peace and blessings be upon him) would devote the last ten days of Ramadan to deeds and characteristics that he did not practice in the rest of the month. We would like Honorable Shaykh Muhammad to inform our listeners about these deeds. May Allah reward you with good?

Answer : In the name of Allah, the Most Gracious, the Most Merciful. Praise be to Allah, Lord of the worlds. May Allah send prayers and blessings upon our Prophet Muhammad, his family, his Companions, and those who follow them in excellence until the Day of Judgment.
The most important thing I dedicate these ten days to is i'tikaf (spiritual retreat in the mosque). He would seeking the Night of Decree. So he would remain in the mosque, (peace and blessings be upon him), and not leave it except for what was absolutely necessary. But he would perform i'tikaf in the mosque. In dedicating himself to the worship of Allah and cutting off contact with people. And the days are only ten. I'tikaf is among the established recommended practices (sunnah) agreed upon by the scholars, but.
It is not like the i'tikaf of some people today, where a person stays in the mosque and his companions who joined him in i'tikaf, or those who did not join him, come to him and they talk a lot about things of no benefit. In reality, this is a waste of time and a waste of the i'tikaf. The one performing i'tikaf should devote himself to the worship of Allah (Mighty and Majestic). But there is no blame on him if he talks about what is necessary, such as giving advice to someone who needs it, or sitting in a circle of knowledge, or talking to some of his family in a way that promotes reconciliation and spreading affection. As it was reported from the Prophet (peace and blessings be upon him) that came to him in his mosque while he was in i'tikaf, so he talked to her for a while. Then she stood up to leave, so he stood up with her to see her off (peace and blessings be upon him), meaning to accompany her, as we express it.
So, among the things that distinguish these last ten days is that he (peace and blessings be upon him) would keep the entire night awake, meaning he would not sleep (may Allah's prayers and peace be upon him); he would occupy it with tahajjud (the late-night voluntary prayer), recitation, and other things that bring one closer to Allah (Blessed and Exalted is He). And he would not keep the entire night awake outside of the last ten days.