Jews predate Muslims in Egypt by at least 2000 years.
Ok, leave the Bible aside, it’s known that the population of Alexandria was very Jewish in Ptolemaic times, they being brought there by Ptolemy the Great, about 300BC. So make it 1000 years of continuous residence as reliably attested.
Why did the stars have a square or a triangle in the center. I am not aware of this as being modern Jewish usage. Anyone know?