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navigator.locks — the four-tabs race

Check what actually stuck about the Web Locks API: why a localStorage flag isn't a mutex, what navigator.locks.request() guarantees, and where its job ends and BroadcastChannel's begins.

questions8
pass mark70%
resultsat the end

No account needed. Answer all 8 questions, then see your score with every answer explained and a reference to the spec or MDN — pass and you can claim a certificate.