Earlier quoted context omitted.
ROFL Signal uses centralized server with closed source (they hidden code for one year until they finally gave up when users nagged them, nobody knows what they did during that year), Signal requires your phone number, Signal doesn't allow third party apps officially and tried to push some shady crypto, I mean how many red flags you need to avoid such POS app?
The Signal client has always been open source: you can inspect precisely what the client is sending to the server (if you trust the source). If you're not sending undesirable information from the client to the server, no amount of closed source-ness of the server is going to get that from you. Signal has always been transparent about what information get sent to the server: https://signal.org/blog/private-contact-dis…
speaking of dense exotic matter https://en.wikipedia.org/wiki/White_dwarf