Name with gear icon in Chrome network requests table

Question

(30119999.xml in pic1, has a gear mark pre name)

I set this request in Web Worker, response data is ok and I terminated it in onmessage callback

but why the request always in pending and can't preview, please help.

pseudocode:

const workerBlob = new Blob([`onmessage = function (event) {
    const xhr = new XMLHttpRequest();
    xhr.addEventListener('load', function () {
        postMessage(xhr.response);
    });
    xhr.open('GET', event.data.url, true);
    xhr.send();
}`], { type: 'application/javascript' });
const workerURL = URL.createObjectURL(workerBlob);
const worker = new Worker(workerUrl);
worker.postMessage({url});
worker.onmessage = (message) => {
    // do something
    worker.terminate();
};

Answer 1

According to Debugging Service Workers :

The gear icon signifies that these requests came from the Service Worker itself. Specifically, these are the requests being made by the Service Worker's install handler to populate the offline cache.