Earlier quoted context omitted.
AFAIK they do allow enforcement of criminal warrants for anything violent. They also don't and can't prevent federal agents from doing anything. They just don't actively cooperate or enforce immigration law with their own police. Also worth noting that they adopted sanctuary status in 1989 which preceded their massive rise in prosperity. It seems unlikely to be a factor in problems of the last 5 years.
News article: https://dailycaller.com/2020/02/19/san-francisco-not-coopera... The city has a "rapid response" hotline you can call if you see any ICE agents in the city. I'm not sure what their response is. But they definitely don't work with the agency
They absolutely will enforce warrants for serious crimes. Nor will they prevent federal agents from operating in the city. The rapid response hotline is a private non-profit and not run by the city.
I suggest not relying on conservative propaganda outlets like Daily Caller for your information.