https://www.vox.com/recode/2019/5/3/18527214/8chan-poway-synagogue-shooting-christchurch-john-earnest

The online platform is a dark, toxic corner of the internet.

On April 27, a 19-year-old man opened fire at a San Diego synagogue, killing one person and injuring three others. The incident took place six weeks after a 28-year-old man murdered 50 people at two mosques in Christchurch, New Zealand. The two have a disturbing commonality: They were both hanging out in the same dark corner of the internet, specifically a site called 8chan.