Mostly "from the river to the sea" (which I know isn't historically anti-semitic but has been used increasingly in the context of denying Israel's right of existence and is now even banned on demonstrations in Germany), they also demand the local university to dismiss Jewish or Israel-friendly professors. I looked at social media presences of some of the organizations that support the demonstrations and some of them downplay or even celebrate the October attacks by Hamas.

That being said, there certainly is public pressure to generalize all pro-Palestinian protests as anti-semitic - which is very wrong and I think it's highly problematic that some politicians fuel this narrative. It does, however, make it even harder for someone with a nuanced point of view to join the protests (not an excuse, just an explanation why the demonstrations become more and more extremist).