Who are "the Strangers" whom the Messenger of Allah, peace and blessings be upon him, mentioned and loved, and when will they appear?

It has not been authentically reported from the Prophet, peace and blessings be upon him, that he foretold about his beloved ones among the Muslims in future times, or that he loved anyone more than his Companions. He described his followers as "his brethren" in the hadith narrated by Abu Hurairah, where he said: "You are my Companions, and our brethren are those who have not yet come." The Companions combined both brotherhood and companionship, and the term companionship [sahabah] holds a higher status.

As for the hadith, "My beloved ones are a people who have not seen me but have believed in me," it is fabricated and not authentic due to two weaknesses in its chain of transmission: Nu'aim bin Salim (or Yaghanam bin Salim) and Uthman bin Abdullah Al-Umawi.