bitcoin/doc/release-notes.md

After branching off for a major version release of Bitcoin Core, use this template to create the initial release notes draft.

The release notes draft is a temporary file that can be added to by anyone. See /doc/developer-notes.md#release-notes for the process.

Create the draft, named "version Release Notes Draft" (e.g. "0.20.0 Release Notes Draft"), as a collaborative wiki in:

https://github.com/bitcoin-core/bitcoin-devwiki/wiki/

Before the final release, move the notes back to this git repository.

version Release Notes Draft

Bitcoin Core version version is now available from:

https://bitcoincore.org/bin/bitcoin-core-*version*/

This release includes new features, 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/

How to Upgrade

If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), 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 might take some time if the datadir needs to be migrated. Old wallet versions of Bitcoin Core are generally supported.

Compatibility

Bitcoin Core is supported and extensively tested on operating systems using the Linux kernel, macOS 10.10+, and Windows 7 and newer. It is not recommended to use Bitcoin Core on unsupported systems.

Bitcoin Core should also work on most other Unix-like systems but is not as frequently tested on them.

From 0.17.0 onwards, macOS <10.10 is no longer supported. 0.17.0 is built using Qt 5.9.x, which doesn't support versions of macOS older than 10.10. Additionally, Bitcoin Core does not yet change appearance when macOS "dark mode" is activated.

In addition to previously-supported CPU platforms, this release's pre-compiled distribution also provides binaries for the RISC-V platform.

Notable changes

New RPCs

• getbalances returns an object with all balances (mine, untrusted_pending and immature). Please refer to the RPC help of getbalances for details. The new RPC is intended to replace getunconfirmedbalance and the balance fields in getwalletinfo, as well as getbalance. The old calls may be removed in a future version.

Updated RPCs

Note: some low-level RPC changes mainly useful for testing are described in the Low-level Changes section below.

• The sendmany RPC had an argument minconf that was not well specified and would lead to RPC errors even when the wallet's coin selection would succeed. The sendtoaddress RPC never had this check, so to normalize the behavior, minconf is now ignored in sendmany. If the coin selection does not succeed due to missing coins, it will still throw an RPC error. Be reminded that coin selection is influenced by the -spendzeroconfchange, -limitancestorcount, -limitdescendantcount and -walletrejectlongchains command line arguments.

Low-level changes

RPC

Tests

• The regression test chain, that can be enabled by the -regtest command line flag, now requires transactions to not violate standard policy by default. Making the default the same as for mainnet, makes it easier to test mainnet behavior on regtest. Be reminded that the testnet still allows non-standard txs by default and that the policy can be locally adjusted with the -acceptnonstdtxn command line flag for both test chains.

Configuration

• An error is issued where previously a warning was issued when a setting in the config file was specified in the default section, but not overridden for the selected network. This change takes only effect if the selected network is not mainnet.

Network

• When fetching a transaction announced by multiple peers, previous versions of Bitcoin Core would sequentially attempt to download the transaction from each announcing peer until the transaction is received, in the order that those peers' announcements were received. In this release, the download logic has changed to randomize the fetch order across peers and to prefer sending download requests to outbound peers over inbound peers. This fixes an issue where inbound peers can prevent a node from getting a transaction.

Wallet

• When in pruned mode, a rescan that was triggered by an importwallet, importpubkey, importaddress, or importprivkey RPC will only fail when blocks have been pruned. Previously it would fail when -prune has been set. This change allows to set -prune to a high value (e.g. the disk size) and the calls to any of the import RPCs would fail when the first block is pruned.

Credits

Thanks to everyone who directly contributed to this release:

As well as everyone that helped translating on Transifex.