Twitter owns Signal App: In November 2011, Whisper Systems announced that it had been acquired by Twitter.

Boom: Looks like Antifa communicates via Signal App: Signal's popularity in the United States has reportedly increased substantially due to the George Floyd protests, particularly among organizers and activists. In June 2020, Signal Foundation co-founder Moxie Marlinspike announced the release of a feature that enables users to blur faces in photos. This new feature was launched after U.S. authorities increased their efforts to monitor the protests.

https://en.wikipedia.org/wiki/Signal_(software)