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    <h1>Repro worker.close() error</h1>
    <pre id="display"></pre>
    <script>
      (() => {
        let worker = new Worker('worker.js')
        let display = document.getElementById('display')

        let failed = false

        worker.addEventListener('message', () => {
          failed = true
          display.innerHTML += 'Test failed! Got a message from worker after close().\n'
        })

        setTimeout(() => {
          if (!failed) {
            display.innerHTML += 'Test succeeded! No message received from worker after close().\n'
          }
        }, 2000)

        worker.postMessage('ping')
      })()
    </script>
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