"The Terrorgram story is part of a much larger 21st century phenomenon. Over the past two decades, massive social networks like X, Facebook and Telegram have emerged as a powerful force for both good and evil. The ability to connect with like-minded strangers helped fuel uprisings like the Arab Spring and Iran’s pro-democracy movements. But it has also aided extremists, including brutal jihadist organizations like the Islamic State group and white supremacists around the world.
Telegram, which is massively popular outside of the U.S., boasted an array of features that appealed to Humber and her fellow Terrorgammers. They could send encrypted direct messages, start big chat groups and create public channels to broadcast their messages. In the span of five years, they grew Terrorgram from a handful of accounts into a community with hundreds of chats and channels focused on recruiting would-be terrorists, sharing grisly videos and trading expertise on everything from assassination techniques to the best ways to sabotage water systems and electrical transmission lines. On one of her many accounts, Humber posted step-by-step instructions for making pipe bombs and synthesizing HMTD, a potent explosive.
Humber went by a series of usernames but was eventually publicly exposed by a group of California activists. ProPublica and FRONTLINE reviewed chat logs — some provided by the Australian anti-facist research organization The White Rose Society — court records and Humber’s other digital accounts to independently confirm her identity."
https://www.propublica.org/article/rise-and-fall-terrorgram-inside-global-online-hate-network-frontline-telegram