I appeared for the screening round of facebook software engineering role (wasn't told about the position or team though). I have an experience of ~8 years. I got rejected in the screeing round itself. After the initial round of discussion I asked for gap of 6 weeks to prepare for screening round. My approach was to get used to as many medium leetcode questions as possible. I practised around 230 LC questions, majorly medium and few easy and couple of hard questions.

In the screening round I was asked a question (I didnt practice it on LC, so not sure if its there on the list of problems) that given a sorted integer array, return the sorted square of those integer array.
eg : input [1,2,3] output [1,4,9] . I missed the corner case of integer overflow and hence was not promoted to the next round .