@hothobbit Encryption is the default w/ Signal, where with Matrix it's opt-in.
I'm not sure if this is still true (tho it was at least two months ago), Matrix has had issues with group chats giving the dreaded "Unable to decrypt: The sender's device has not sent us the keys for this message.", due to the it's federated nature.
New features are looked at from a security point of view before being added to Signal (for instance url links, etc), which isn't the case with Matrix...
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