chromium/content/test/data/accessibility/html/name-calc-focusable.html

<!DOCTYPE html>
<!--
@BLINK-ALLOW:focus*
@EXECUTE-AND-WAIT-FOR:setTabIndex0()
@EXECUTE-AND-WAIT-FOR:setTabIndexMinus1()
@EXECUTE-AND-WAIT-FOR:setFocus()
@EXECUTE-AND-WAIT-FOR:removeTabIndex()
-->
<div>
  <p>Cats
  <p>Dogs
</p>

<script>
const div = document.querySelector('div');
document.title = 'not-focusable-no-name';

function setTabIndex0() {
  div.tabIndex = '0';
  document.title = 'tabindex-0-has-name';
  return 'tabindex-0-has-name';
}

function setTabIndexMinus1() {
  div.tabIndex = '-1';
  document.title = 'tabindex-minus-1-no-name';
  return 'tabindex-minus-1-no-name';
}

function setFocus() {
  div.focus();
  document.title = 'focus-has-name';
  return 'focus-has-name';
}

function removeTabIndex() {
  div.removeAttribute('tabindex');  // This should also blur the element.
  document.title = 'remove-tabindex-no-name';
  return 'remove-tabindex-no-name';
}
</script>