@fribbledom Looking at the consumer documentation https://support.signal.org/hc/en-us/articles/360007061452-Does-Signal-send-my-number-to-my-contacts- there seems to be various problems with the approach. Signal checks existence of phone numbers from the centralised database, even while the notifications itself are generated locally. There doesn't seem to be a way to prevent others from getting notification. Essentially they are data processor.
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