← Stop using the localStorage hack to sync browser tabs. BroadcastChannel does it natively.Quiz
BroadcastChannel API — cross-tab messaging
BroadcastChannel lets any tab, worker, or iframe on the same origin send and receive messages directly, with no localStorage side-channel required. These questions cover the API shape, scope restrictions, data types, browser support, and how it compares to the localStorage+storage-event workaround.
questions9
pass mark70%
resultsat the end
No account needed. Answer all 9 questions, then see your score with every answer explained and a reference to the spec or MDN — pass and you can claim a certificate.