Meta Security Engineer interview questions

I applied on Facebook career portal and was pleasantly surprised (and excited) when contacted (I have a Microsoft tech heavy profile) by their recruiter. Had promptly facilitated telephonic interview (general application security related) and then another phone interview. I was then asked to attend a series of onsite interviews. Did not get an offer but thoroughly enjoyed talking to all the interviewers. These is an amazing bunch of people tackling security issues at an unprecedented scale. I will definitely re apply in the future!