(() => {
  const KEY = "__cab";
  const host = location.hostname;
  if (!host) return;
  chrome.runtime.sendMessage({ cmd: "page", host, top: window === window.top }).then(res => {
    if (!res) return;
    const s = res.scriptlets && res.scriptlets.length ? JSON.stringify(res.scriptlets) : "";
    let prev = null;
    try { prev = localStorage.getItem(KEY); } catch (e) {}
    if (s === (prev || "")) return;
    try {
      if (s) localStorage.setItem(KEY, s);
      else localStorage.removeItem(KEY);
    } catch (e) {}
    if (s) window.dispatchEvent(new CustomEvent(KEY, { detail: s }));
  }).catch(() => {});
})();