Petrit Latifi
According to this doctorate written by Leontije Pavlovic in 1965, the Brankovic family were not ethnic Serbs. Translated:

“BORBE (MAKSIM) BRANKOVIĆ (died 1516)
Borgia was born in Albania in 1461 and spent his childhood in Italy. As a Hungarian nobleman, he was the titular despot of Serbia from 1486 to 1495. He married Isabella of the Aragonese dynasty of Naples, but divorced her and around 1497 he became a monk and took the name Maxim. He later became Archbishop of Wallachia, and from 1513 Metropolitan of Belgrade and Srem. With his death on 18 January 1516, the Branković family became extinct. He founded the Krušedol monastery and restored some of the Fruška Gora monasteries.
In the manuscript Minya of Decani for January (no. 177/292. l. 144.a) Maxim is called “Archbishop Maxim the New, former Serbian despot”. (Fig. 30.) and in the Roman Serbian “holy father our Archbishop Maxim the New, former Serbian despot”.1) In addition, Archbishop Maxim is called in 1686 or 1687 “the Serbian miracle worker” 2).
His prologue was printed in the Romani³) and Moscow Serbian editions as well as in the Glasnik5) of the DSS in 1859. It records that Maxim was a descendant of Simeon Nemanja and that his parents were Stefan and Angelina Branković. It is particularly emphasized that Maxim was born in Tubina, that he renounced the despotic position, that he did not marry,6) (?) but became a monk.
When the Catholic Ivan Berislavić, who was intolerant of the cult of Stephen the Blind, came to the Branković house through marriage, Maxim and his mother took his father and brother’s relics to Wallachia. Later, around 1509, he returned them to Kupinovo. Later, he built the Krušedol monastery and transferred their relics there. Maxim died on January 18 (1516).
According to the life, at the hour of his death, the Patriarchs of Alexandria Athanasius and Cyril, who are celebrated on that day, appeared to him. After many signs and appearances in a dream, 7 years after his death (i.e. 1522/3), his tomb was opened and his whole and fragrant body was found in it, along with his burial clothes. Then the healing of the sick is described.”