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Put a call out to find people to help you test. This could be between 3-10 people depending on the size and scope of the release. You want to try to give them a timeline and a target due date. Most testers are busy but able to help out with some notice. Accessibility is particularly tricky to schedule because of limited number of testers, complexity of the test, and timing of the testing. Some places to find testers: repo-managers, ux (accessibility).
Conducting testing:
Bug reports:
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