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+= Mercurial 6.6rc0 =
+
+As usual, a *lot* of patches don't make it to this list.
+
+== New Features ==
+ * rust-config: add support for default config items
+ * rhg: add config defaults to configitems.toml
+ * rhg: support "status FILE"
+ * rhg: support rhg files [FILE]
+ * commands: add admin namespace
+ * admin-command: add verify command
+ * debug-delta-chain: add options to control what we compute
+ * Added some caching for uncompressed revlog chunks that speed up some operations
+
+== New Experimental Features ==
+
+== Bug Fixes ==
+ * Improve OpenVMS support
+ * byteify-strings: passe sysstr to attr function and wrapper
+ * journal: track bookmark deletion
+ * transaction: actually delete file created during the transaction on rollback
+ * pull: avoid referencing a variable before it is initialized
+ * rust-filepatterns: also normalize RelPath
+ * narrow: hoist a variable to a higher level to avoid use-before-init warning
+ * convert: stabilize subversion date sorter
+ * run-tests: detect HGWITHRUSTEXT value
+ * censor: accept censored revision during upgrade
+ * rust-matchers: fix quadratic complexity in `FileMatcher`
+ * unstable: do not consider internal phases when computing unstable
+ * Still a whole bunch of Python 2 -> 3 migration leftovers
+
+== Backwards Compatibility Changes ==
+ * perf: display all timing by default
+ * infinitepush: drop the extension
+ * debug-delta-chain: print less data by default
+
+== Internal API Changes ==
+
+ * The revlog interface has been significantly cleaned up.
+ * configitems: add `documentation` field
+ * configitems: declare items in a TOML file
+ * configitems: move blackbox's config items to the new configitems.toml
+ * path-suboption: deprecated specifying the attributes as bytes
+ * pycompat: deprecate using bytes
+ * check-code: drop the `safehasattr` rule
+ * safehasattr: drop usage in favor of hasattr
+ * rust: add `UncheckedRevision` type
+ * rust: implement the `Graph` trait for all revlogs
+ * rust: make `Revision` a newtype
+ * perf: change the way we approach revlog reading
+ * perf: ensure all readlog's reading is done within a `reading` context
+ * delta-chain: move the debugdeltachain command in revlogutils
+
+== Miscellaneous ==
+