const filter = browser.webRequest.filterResponseData(e.requestId);
let buffers = null; //result

// onNext, onDone, onError
filter.ondata = (event) => {
  const data = event.data;
  if (buffers === null) {
    buffers = new Uint8Array(data); return;
  }
  const buffer = new Uint8Array(buffers.byteLength + data.byteLength);
  //v 将响应分段数据收集拼接起来，在完成加载后整体替换。这可能会改变浏览器接收数据分段渲染的行为。
  buffer.set(buffers); buffer.set(new Uint8Array(data), buffers.buffer.byteLength);
  buffers = buffer;
}

filter.onstop = () => {
  if (buffers === null) { filter.close(); return; }

  for (let item of rule) { //< 缓存实例，减少开销
    const encoding = item.encoding || "UTF-8";
    try {
      const _text = this._textDecode(encoding, buffers.buffer);
      const text = item._func(_text, detail);
      if (typeof text === 'string' && text !== _text) { buffers = this._textEncode(encoding, text); }
    } catch (e) { console.error(e); }
  }

  filter.write(buffers.buffer);
  buffers = null;
  filter.close();
}

filter.onerror = () => { buffers = null; }

filter.onstop = () => {
  if (buffers === null) { filter.close(); return; }
  onRequestData(buffers.buffer);
  filter.write(buffers.buffer);
  buffers = null; //< 这个 dispose 必须要做，可没 GC 帮你削对象了
  filter.close();
}

if (p) {
  f();
}
cont();

if (!p) return; // 或者 break 之类能够跳过下面的 else branch 的东西
f();
cont();

(br.not b) a (jmp c) b c

(br.if a) b (jmp c) a c

if (!p) return; f(); cont();
(test p) (br.not return) (call f) (call cont) return

if (p) f(); else f1();
(test p) (br.not f1) (call f) (jmp cont)  f1 (call f1) cont