What do you think is the difference between santa claus and a jew ? Santa comes down the chimney.
What does that joke mean about the Jews?
It's just a joke. Santa Claus is coming down the chimney into the fireplace to get you a gift while jews burn alive.
The holocaust was a traumatizing event for many people and it can be hurtful to be reminded of it even by mentioning or joking about it. You should go to a holocaust museum to understand what happened there and why it can be hurtful.
Let's love and keep this shit positive.
If you want to love and be positive, it's important to avoid telling hurtful and insensitive jokes.