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<!DOCTYPE html>
<meta charset="utf-8">
<script src="foo" type="text/javascript"></script>
<script>
// Note: this file gets loaded twice in the course of this test: first, in an
// iframe hosted in the top-level test; and second, in an <object> inside that
// iframe's document. (The object element gets created dynamically in the
// script below.)
window.onload = () => {
  // For efficiency: check our window.location, to be sure we only run this
  // logic in the iframe, and *not* in the <object> that ends up getting loaded
  // with the same URL plus a "?" at the end:
  let locationStr = "" + location;
  if (!locationStr.endsWith("?")) {
    window.print();
    // Add an object whose location is set to '?' (which means our same
    // base URL plus a "?" character):
    let a = document.createElement("object");
    a.data = "?";
    document.documentElement.appendChild(a)
  } else if (parent.parent && parent.parent.iframeStepComplete) {
    // We're the nested document in the `<object>` tag that was created above.
    // Signal the outer document (our grandparent) that we've completed the
    // step of loading this inner object document.
    parent.parent.iframeStepComplete();
  }
}
window.onafterprint = () => {
  // We've finished printing; signal to our outer document that we've completed
  // that step.
  parent.iframeStepComplete();
}
</script>