TT #70 · Parashas Vayechi · Passuk 50:11
And when the Canaanite inhabitants of the land saw the mourning at Goren ha-Atad, they said, “This is a solemn mourning on the part of the Egyptians.” That is why it was named Abel-mizraim, which is beyond the Jordan.
Torah Temimah cites Yerushalmi Sotah 1:10.
English: “This is a grievous mourning for Egypt.” Rabbi Yuden said in the name of Rabbi Shalom: This teaches that they pointed with their fingers and said, “This is a grievous mourning for Egypt.”
Midrashic reading of the phrase “mourning for Egypt.”
The Canaanites’ words are presented as a public recognition that Jacob’s death was a profound loss for Egypt.