Merge bitcoin#31630: doc: Archive 28.1 release notes

bb5f76e doc: Archive 28.1 release notes (Ava Chow)

Pull request description:

ACKs for top commit:
  rkrux:
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Tree-SHA512: f146f760f61154627df6109fa4cceb9717e7bfae8c04c82a0562a458a26f47036e3831374108d1261bbc35f3ff51615840c8f7e074d0f83ed3489b224eb6ec07

Author: glozow

doc/release-notes/release-notes-28.1.md

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+Bitcoin Core version 28.1 is now available from:
+
+  <https://bitcoincore.org/bin/bitcoin-core-28.1>
+
+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 in some cases), then run the
+installer (on Windows) or just copy over `/Applications/Bitcoin-Qt` (on macOS)
+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.
+
+Running Bitcoin Core binaries on macOS requires self signing.
+```
+cd /path/to/bitcoin-28.x/bin
+xattr -d com.apple.quarantine bitcoin-cli bitcoin-qt bitcoin-tx bitcoin-util bitcoin-wallet bitcoind test_bitcoin
+codesign -s - bitcoin-cli bitcoin-qt bitcoin-tx bitcoin-util bitcoin-wallet bitcoind test_bitcoin
+```
+
+Compatibility
+==============
+
+Bitcoin Core is supported and extensively tested on operating systems
+using the Linux Kernel 3.17+, macOS 11.0+, 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.
+
+Notable changes
+===============
+
+### P2P
+
+- When the `-port` configuration option is used, the default onion listening port will now
+  be derived to be that port + 1 instead of being set to a fixed value (8334 on mainnet).
+  This re-allows setups with multiple local nodes using different `-port` and not using `-bind`,
+  which would lead to a startup failure in v28.0 due to a port collision.
+
+  Note that a `HiddenServicePort` manually configured in `torrc` may need adjustment if used in
+  connection with the `-port` option.
+  For example, if you are using `-port=5555` with a non-standard value and not using `-bind=...=onion`,
+  previously Bitcoin Core would listen for incoming Tor connections on `127.0.0.1:8334`.
+  Now it would listen on `127.0.0.1:5556` (`-port` plus one). If you configured the hidden service manually
+  in torrc now you have to change it from `HiddenServicePort 8333 127.0.0.1:8334` to `HiddenServicePort 8333
+  127.0.0.1:5556`, or configure bitcoind with `-bind=127.0.0.1:8334=onion` to get the previous behavior.
+  (#31223)
+- #30568 addrman: change internal id counting to int64_t
+
+### Key
+
+- #31166 key: clear out secret data in DecodeExtKey
+
+### Build
+
+- #31013 depends: For mingw cross compile use `-gcc-posix` to prevent library conflict
+- #31502 depends: Fix CXXFLAGS on NetBSD
+
+### Test
+
+- #31016 test: add missing sync to feature_fee_estimation.py
+- #31448 fuzz: add cstdlib to FuzzedDataProvider
+- #31419 test: fix MIN macro redefinition
+- #31563 rpc: Extend scope of validation mutex in generateblock
+
+### Doc
+
+- #31007 doc: add testnet4 section header for config file
+
+### CI
+
+- #30961 ci: add LLVM_SYMBOLIZER_PATH to Valgrind fuzz job
+
+### Misc
+
+- #31267 refactor: Drop deprecated space in `operator""_mst`
+- #31431 util: use explicit cast in MultiIntBitSet::Fill()
+
+Credits
+=======
+
+Thanks to everyone who directly contributed to this release:
+
+- fanquake
+- Hennadii Stepanov
+- laanwj
+- MarcoFalke
+- Martin Zumsande
+- Marnix
+- Sebastian Falbesoner
+
+As well as to everyone that helped with translations on
+[Transifex](https://www.transifex.com/bitcoin/bitcoin/).