So the words "happy chanukah" were visible, I had to click a button to see the menorah with the caterpillar.

I'm going out on a limb here, BUT perhaps Twitter was flagging the combination of the menorah WITH the caterpillar. Imagine, a Jewish symbol with a pig head - that might be offensive to Jewish people.

Perhaps Twitter speculates that the insect (a non kosher food) with the menorah is making it unclean - and thus offensive. Perhaps. Again, I'm not certain. I'm also not offended. Nor am I Jewish. And I don't eat caterpillars.