Andrew's git / gitweb.git / Documentation/config/showbranch.txt
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Documentation / config / showbranch.txton commit ref-filter.c: find disjoint pattern prefixes (b31e268)
   1showBranch.default::
   2        The default set of branches for linkgit:git-show-branch[1].
   3        See linkgit:git-show-branch[1].