Salam
Let me refute this favorism thing
Bukhari 3733, The Prophet said, 'If a reputable man amongst the children of Bani Israel committed a theft, they used to forgive him, but if a poor man committed a theft, they would cut his hand. But I would cut even the hand of Fatima (i.e. the daughter of the Prophet) if she committed a theft."
So he would cut off the hand of his daugjter for theft. So much for favoritism
This hadith is very sahih and is mentiikned many times more:
Bukhari 6788 muslim 1689 bukhari 6787 muslim 1688 a and many more see the whole list here:
https://sunnah.com/search/?q=Fatima+theftBukhari 6780: During the lifetime of the Prophet (ﷺ) there was a man called `Abdullah whose nickname was Donkey, and he used to make Allah's Messenger (ﷺ) laugh. The Prophet (ﷺ) lashed him because of drinking (alcohol). And one-day he was brought to the Prophet (ﷺ) on the same charge and was lashed. On that, a man among the people said, "O Allah, curse him ! How frequently he has been brought (to the Prophet (ﷺ) on such a charge)!" The Prophet (ﷺ) said, "Do not curse him, for by Allah, I know for he loves Allah and His Apostle."
He knew this guy loved him and allah swt but still he punished him so far for favoritism.
Quran 4:135: O you who have believed, be persistently standing firm in justice, witnesses for Allah, even if it be against yourselves or parents and relatives. Whether one is rich or poor, Allah is more worthy of both. So follow not [personal] inclination, lest you not be just. And if you distort [your testimony] or refuse [to give it], then indeed Allah is ever, with what you do, Acquainted.
So much for favoritism
The following ahadith destroy the idea of favoritism:
Uqbah ibn Amir reported: The Messenger of Allah, peace and blessings be upon him, said, “No one is better than anyone else except by religion or good deeds. It is sufficient evil for a man to be profane, vulgar, greedy, or cowardly.”
Source: Shu’b al-Iman 4767
Grade: Sahih (authentic) according to Al-Albani
Muhammad saws made it clear arab has no superiority so far for favoritism
Jabir ibn Abdullah reported: The Messenger of Allah, peace and blessings be upon him, addressed us during the middle of the day at the end of the pilgrimage in the farewell sermon. The Prophet said, “O people, your Lord is one and your father Adam is one. There is no virtue of an Arab over a foreigner, nor a foreigner over an Arab, and neither white over black nor black over white, except by righteousness. Have I not delivered the message?” They said, “Of course, O Messenger of Allah.” The Prophet said, “Let the witness inform those who are absent.”
Source: Shu’ab al-Imān 4706
Grade: Sahih (authentic) according to Al-Albani
And muhammad saws was against tribalism The Prophet said, “No, but rather it is tribalism that he supports his people in wrongdoing.”
Source: Sunan Ibn Mājah 3949
Grade: Hasan (fair) according to Ibn Muflih
Also there is a kind of well knwon hadith to slander the prophet saws where he says that if the people do tribalism like in the time of jahiliyya tell him to bite his fathers penjs.
This hadith is recorded in many hadith works including Musnad Ahmad, Sunan al-Kubra of an-Nasa’i and Mushkil al-Athar of at-Tahawi. It is also quoted in Shia sources; see for instance: al-Majlisi, Muhammad Baqir, Bihar al-Anwar, Vol.32, 91. Al-Majlisi also quotes another narration attributed to ‘Ali with a similar wording.
Before you say it is filthy it has been answered:
http://www.letmeturnthetables.com/2013/08/explained-bite-father-penis-hadith.html?m=1