It pains me to mention this but I don't think it's responsible not to:
https://github.com/meshtastic/firmware/issues/4030
At time of writing (2025-09-27, plus or minus a timezone), there does not appear to be any serious attempt to secure application-layer message contents. (At least, not yet)
My hope is that this cool new radio link option will still gain traction and grow and develop without painting itself into a corner, security-wise.
To wit- security hints on https://en.wikipedia.org/wiki/OSI_model have improved substantially since my last readthrough.
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