Chat Control 2.0: what if Signal supports user-made Add-ons, one which encrypts all messages? Could that circumvent Chat Control 2.0?

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Signal can then claim it has no control over what user-made Add-ons are installed and used for. They just support the framework, which is not illegal, just like media players support playing illegal content but don't create such content.

For people out of the loop: EU soon likely enacts Chat Control 2.0 which will force chat services to hand over keys so governments can read all your personal messages.