@aniya.jaskolski 
To test the content of an iframe using Jest, you can use the following steps:
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import "@testing-library/jest-dom/extend-expect";
test("iframe is present in the document", () => {
  const iframe = document.querySelector(".iframe-class");
  expect(iframe).toBeInTheDocument();
});
 | 
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test("content of iframe is correct", () => {
  const iframe = document.querySelector(".iframe-class");
  const iframeDocument = iframe.contentWindow.document;
  
  expect(iframeDocument.body.innerHTML).toContain("Expected content");
});
 | 
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test("content of iframe is correct", async () => {
  const iframe = document.querySelector(".iframe-class");
  const iframeDocument = iframe.contentWindow.document;
  // Delay for 1 second to allow content to fully load
  await new Promise(resolve => setTimeout(resolve, 1000));
  
  expect(iframeDocument.body.innerHTML).toContain("Expected content");
});
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By following these steps, you can effectively test the content of an iframe using Jest in your unit tests.