Bug 41454: Move focus after calling openPreferences for a sub-category.

  }

  let header = getClosestDisplayedHeader(element);

  // We assign a tabindex=-1 to the element so that we can focus it. This allows

  // us to move screen reader's focus to an arbitrary position on the page.

  // See tor-browser#41454 and bug 1799153.

  element.setAttribute("tabindex", "-1");

  // The element is not always immediately focusable, so we wait until the next

  // loop.

  setTimeout(() => {

    Services.focus.setFocus(element, Services.focus.FLAG_NOSCROLL);

    element.removeAttribute("tabindex");

  });

  scrollContentTo(header);

  element.classList.add("spotlight");

}