Huge Mk4 Release! Version 5.1.1 (was 5.1.0)

New Features

  • “MicroSD card as Second Factor”. Specially marked MicroSD card must be already inserted when (true) PIN is entered, or else seed is wiped. Add, remove and check cards in menu: Settings -> Login Settings -> MicroSD 2FA

  • Import TAPSIGNER encrypted backup as main or ephemeral seed, for PSBT signing. This is a great way to safely use the key previously held inside a TAPSIGNER, because the COLDCARD can take over the signing that used to be done by the card.

  • Detached Bitcoin signature files for most exports.

    • Files exported are now signed with a detached signature. Look for a .sig file with the same name, and verify signature with your favourite Bitcoin tools. See “Signed Exports” in docs/msg-signing.md for more information.
    • Coldcard can now verify signed files:
      • SD card and Virtual disk Advanced/Tools -> File Management -> Verify Sig File
      • NFC Advanced/Tools -> NFC Tools -> Verify Sig File
    • Learn more here
    • Related new website: Check your Bitcoin signatures here

Enhancements

  • Address Explorer:
    • Application-specific derivation paths in Address Explorer -> Applications
    • Bugfix: Change value was ignored when generating addresses file
  • Imports:
    • Add import multisig wallet via Virtual Disk
    • Add import extended private key via Virtual Disk and via NFC
    • Import seed in compact/truncated form (just 3-4 letters of each seed word)
    • Import extended private key as ephemeral seed
  • Export:
    • Samourai POST-MIX and PRE-MIX descriptor export options added
    • Lily Wallet added
    • Ability to export all supported wallets via NFC (instead of SD card only)
    • Change electrum export file name from ‘new-wallet.json’ to ‘new-electrum.json’
    • Allow export of Wasabi skeleton for Bitcoin Regtest.
  • Backup Enhancement:
    • Option to save the backup file’s encryption password for next backup. Then next backup is quick and simple: no need to record yet another 12 words.
  • During seed generation from dice rolls, enforce at least 50 rolls for 12 word seeds, and 99 rolls for 24 word seeds. Statistical distribution check

  • Single signature wallet generic descriptor export Advanced -> Export Wallet -> Descriptor. Both new format with internal/external in one descriptor <0;1> and standard with two descriptors are supported. added to prevent users from generating low-entropy seeds by rolling same value repeatedly.

  • Docs: Add docs/rolls12.py script for verifying dice rolls math for 12 word seeds.

Bug Fixes

  • Offer import/export from/to Virtual Disk in UI even if SD Card is inserted.
  • Recalculate extended key saved in settings upon chain change (BTC, XTN, XRT).
  • Provide correct derivation path (m/84’/1’/0’) for testnet Wasabi export.
  • Properly display UX checkmark only if testnet (XTN, XRT) is enabled in Settings- > Danger Zone -> Testnet Mode.
  • v5.1.0 would not install over MicroSD; 5.1.1 was made to replace it. Same functionality.

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