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Help guarantee that every feature in each release is as well-tested as possible, in such a way to minimize the introduction of last-minute bugs;
Help the Product Working Group communicate with whoever is doing the testing, so that the latter effort can be factored into the plan for upcoming releases.
And finally:
How much of the testing should be delegated to the development teams? To the reviewers? To a dedicated testing team?
Part I. Overview of the current community testing strategy
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