doc/release-notes/release-notes-0.21.1.md
Bitcoin Core version 0.21.1 is now available from:
https://bitcoincore.org/bin/bitcoin-core-0.21.1/
This minor release includes various bug fixes and performance improvements, as well as updated translations.
Please report bugs using the issue tracker at GitHub:
https://github.com/bitcoin/bitcoin/issues
To receive security and update notifications, please subscribe to:
https://bitcoincore.org/en/list/announcements/join/
If you are running an older version, shut it down. Wait until it has completely
shut down (which might take a few minutes in some cases), then run the
installer (on Windows) or just copy over /Applications/Bitcoin-Qt (on Mac)
or bitcoind/bitcoin-qt (on Linux).
Upgrading directly from a version of Bitcoin Core that has reached its EOL is possible, but it might take some time if the data directory needs to be migrated. Old wallet versions of Bitcoin Core are generally supported.
Bitcoin Core is supported and extensively tested on operating systems using the Linux kernel, macOS 10.12+, and Windows 7 and newer. Bitcoin Core should also work on most other Unix-like systems but is not as frequently tested on them. It is not recommended to use Bitcoin Core on unsupported systems.
From Bitcoin Core 0.20.0 onwards, macOS versions earlier than 10.12 are no longer supported. Additionally, Bitcoin Core does not yet change appearance when macOS "dark mode" is activated.
Included in this release are the mainnet and testnet activation parameters for the taproot soft fork (BIP341) which also adds support for schnorr signatures (BIP340) and tapscript (BIP342).
If activated, these improvements will allow users of single-signature scripts, multisignature scripts, and complex contracts to all use identical-appearing commitments that enhance their privacy and the fungibility of all bitcoins. Spenders will enjoy lower fees and the ability to resolve many multisig scripts and complex contracts with the same efficiency, low fees, and large anonymity set as single-sig users. Taproot and schnorr also include efficiency improvements for full nodes such as the ability to batch signature verification. Together, the improvements lay the groundwork for future potential upgrades that may improve efficiency, privacy, and fungibility further.
Activation for taproot is being managed using a variation of BIP9 versionbits called Speedy Trial (described in BIP341). Taproot's versionbit is bit 2, and nodes will begin tracking which blocks signal support for taproot at the beginning of the first retarget period after taproot’s start date of 24 April 2021. If 90% of blocks within a 2,016-block retarget period (about two weeks) signal support for taproot prior to the first retarget period beginning after the time of 11 August 2021, the soft fork will be locked in, and taproot will then be active as of block 709632 (expected in early or mid November).
Should taproot not be locked in via Speedy Trial activation, it is expected that a follow-up activation mechanism will be deployed, with changes to address the reasons the Speedy Trial method failed.
This release includes the ability to pay taproot addresses, although payments to such addresses are not secure until taproot activates. It also includes the ability to relay and mine taproot transactions after activation. Beyond those two basic capabilities, this release does not include any code that allows anyone to directly use taproot. The addition of taproot-related features to Bitcoin Core's wallet is expected in later releases once taproot activation is assured.
All users, businesses, and miners are encouraged to upgrade to this release (or a subsequent compatible release) unless they object to activation of taproot. If taproot is locked in, then upgrading before block 709632 is highly recommended to help enforce taproot's new rules and to avoid the unlikely case of seeing falsely confirmed transactions.
Miners who want to activate Taproot should preferably use this release
to control their signaling. The getblocktemplate RPC results will
automatically be updated to signal once the appropriate start has been
reached and continue signaling until the timeout occurs or taproot
activates. Alternatively, miners may manually start signaling on bit 2
at any time; if taproot activates, they will need to ensure they update
their nodes before block 709632 or non-upgraded nodes could cause them to mine on
an invalid chain. See the versionbits
FAQ for
details.
For more information about taproot, please see the following resources:
Technical specifications
Popular articles;
Development history overview
Other
*ifaddrs (fanquake)feature_taproot (brunoerg)Thanks to everyone who directly contributed to this release:
As well as to everyone that helped with translations on Transifex.