const behavior = "smooth";

scrapbox.PageMenu.addItem({
  title: "Scroll to Top",
  onClick: () => window.scrollTo({top: 0, behavior})
});

scrapbox.PageMenu.addItem({
  title: "Scroll to Bottom",
  onClick: () => {
    const editor = $("#editor");
    const top = editor.offset().top + editor.outerHeight(true);
    window.scrollTo({top, behavior});
  }
});