Version 4.1.2 Released (More QR Codes)

Jul 28, 2021

Shows QR code with BIP-85 derived entropy value if you press (3) while value shown on-screen. Thanks to @opennoms for idea. Works with 12/18/24-words, XPRV, privatekey and even hex cases.
Offer to show QR in other places:
- Coldcard’s main XPUB, in Advanced > View Identity
- Seed words, during picking process (before the quiz)
- Stored seed words: Advanced > Danger Zone > Seed Functions > View Seed Words
- TXID of just-signed transaction (64 hex digits)
- Encryption password for the system backup file (12 words)
We now grind a nonce so that our signatures are always 71 bytes or shorter. This may save a byte in transaction size, and makes our signatures identical to those produced by Bitcoin Core, improving anonymity on-chain. Thanks to @craigraw for detecting this.

Bug Fixes

On a blank Coldcard, after importing a seed phrase using the Seed XOR feature, the main menu was not updated to show system is “Ready To Sign”.
Red caution light could happen (a false positive) if a specific sequence of firmware upgrades and reboots occured in the right order. Issue could only occur once during lifetime of any particular Coldcard.