http://uwb25d43nnzerbozmtviwn7unn7ku226tpsjyhy5n4st5cf3d4mtflqd.onion/posts/e2ee/index.html
Servers have the records of the message queues and any undelivered encrypted messages — no data is stored that links the queues or messages to particular users, and the data which is stored is not very useful without access to the user's device. SimpleX Chat will work with Tor if used on an operating system that forces it to, such as Whonix or Tails.