Test sending hmac crypto keys via postMessage to a worker. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS All checks passed in worker PASS key.type is 'secret' PASS key.extractable is true PASS key.algorithm.name is 'HMAC' PASS key.algorithm.length is 128 PASS key.algorithm.hash.name is 'SHA-1' PASS key.usages is ["sign", "verify"] PASS bytesToASCIIString(exportedKey) is rawKeyAscii PASS successfullyParsed is true TEST COMPLETE