zcashd/doc/release-notes.md

(note: this is a temporary file, to be added-to by anybody, and moved to release-notes at release time)

Notable changes

RPC Changes

• getdeprecationinfo has several changes:
  • It now returns additional information about currently deprecated and disabled features.
  • A new end_of_service object that contains both the block height for end-of-service and the estimated time that the end-of-service halt is expected to occur. Note that this height is just an approximation and will change over time as the end-of-service block height approaches, due to the variability in block times. The end_of_service object is intended to replace the deprecationheight field; see the Deprecations section for additional detail.
  • This RPC method was previously only available for mainnet nodes; it is now also available for testnet and regtest nodes, in which case it does not return end-of-service halt information (as testnet and regtest nodes do not have an end-of-service halt feature.)
• Several z_sendmany failures have moved from synchronous to asynchronous, so while you should already be checking the async operation status, there are now more cases that may trigger failure at that stage.
• The AllowRevealedRecipients privacy policy is now required in order to choose a transparent change address for a transaction. This will only occur when the wallet is unable to construct the transaction without selecting funds from the transparent pool, so the impact of this change is that for such transactions, the user must specify AllowFullyTransparent.
• The estimatepriority RPC call has been removed.

Changes to Transaction Fee Selection

• The -sendfreetransactions option has been removed. This option used to instruct the wallet's legacy transaction creation APIs (sendtoaddress, sendmany, and fundrawtransaction) to use a zero fee for "small" transactions that spend "old" inputs. It will now cause a warning on node startup if used.

Changes to Block Template Construction

• The block template construction algorithm no longer favours transactions that were previously considered "high priority" because they spent older inputs. The -blockprioritysize config option, which configured the portion of the block reserved for these transactions, has been removed and will now cause a warning if used.

Removal of Priority Estimation

• Estimation of "priority" needed for a transaction to be included within a target number of blocks, and the associated estimatepriority RPC call, have been removed. The format for fee_estimates.dat has also changed to no longer save these priority estimates. It will automatically be converted to the new format which is not readable by prior versions of the software.

Deprecations

The following features have been deprecated, but remain available by default. These features may be disabled by setting -allowdeprecated=none. 18 weeks after this release, these features will be disabled by default and the following flags to -allowdeprecated will be required to permit their continued use:

• deprecationinfo_deprecationheight: The deprecationheight field of getdeprecationinfo has been deprecated and replaced by the end_of_service object.