+ * "git commit --help" said "--no-verify" is only about skipping the
+ pre-commit hook, and failed to say that it also skipped the
+ commit-msg hook.
+ (merge def480f os/no-verify-skips-commit-msg-too later to maint).
+
+ * "git merge" in Git v2.9 was taught to forbid merging an unrelated
+ lines of history by default, but that is exactly the kind of thing
+ the "--rejoin" mode of "git subtree" (in contrib/) wants to do.
+ "git subtree" has been taught to use the "--allow-unrelated-histories"
+ option to override the default.
+ (merge 0f12c7d da/subtree-2.9-regression later to maint).
+
+ * The build procedure for "git persistent-https" helper (in contrib/)
+ has been updated so that it can be built with more recent versions
+ of Go.
+ (merge accb613 pm/build-persistent-https-with-recent-go later to maint).
+
+ * There is an optimization used in "git diff $treeA $treeB" to borrow
+ an already checked-out copy in the working tree when it is known to
+ be the same as the blob being compared, expecting that open/mmap of
+ such a file is faster than reading it from the object store, which
+ involves inflating and applying delta. This however kicked in even
+ when the checked-out copy needs to go through the convert-to-git
+ conversion (including the clean filter), which defeats the whole
+ point of the optimization. The optimization has been disabled when
+ the conversion is necessary.
+ (merge 06dec43 jk/diff-do-not-reuse-wtf-needs-cleaning later to maint).
+