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maint-x.y: A branch started when a vX.Y release (internal or external) is made and used to provide updates and bug fixes for that release. A.k.a "release branch".
Examples:
maint-01.0 - contains updates and bug fixes to v0v1.0
maint-2.0 .1 - contains updates and bug fixes to v0v2.10
There is no such thing as the "maint-0.0.1" branch.
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