Why does Puppeteer's `page.evaluate` return empty objects with `querySelectorAll`?

Puppeteer Evaluated QuerySelectorAll Returning Empty Objects

When using Puppeteer's page.evaluate function to query page elements with querySelectorAll, you may encounter an issue where the returned array contains empty objects. This occurs because JavaScript objects are not inherently JSON-serializable.

One potential solution is to extract specific data from the elements, ensuring it can be serialized into JSON. For instance, if you're interested in the href attribute of elements, you can modify your code as follows:

const list = await page.evaluate((sel) => {
  let elements = Array.from(document.querySelectorAll(sel));
  let links = elements.map(element => element.href);
  return links;
}, sel);

This code will return an array of strings representing the href attributes of the selected elements, which can be easily serialized and printed.

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