What is deliberately not here

Shamir secret sharing (SLIP-39) is not offered for seed generation. It splits a single point of failure into a more complicated single point of failure, the implementations are less widely reviewed than multisig, and recovery depends on tooling that may not exist in ten years. Use a multisig quorum instead: the failure modes are better understood, the recovery path is plain BIP-39 plus a descriptor, and other vendors' hardware can hold the other keys.

nullroute will support SLIP-39 import in a later phase, so you can move a Trezor Shamir backup onto the device. It will not generate one.

No entropy is ever taken from the frontend. crypto.getRandomValues() is never called in browser JavaScript for anything security relevant. The frontend collects dice keystrokes and displays results. All entropy collection and all seed derivation happens in the daemon. See INV-KEY-1.

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