old_contents: export default ({ app }) => {
    if (process.env.NODE_ENV !== 'production') { return false }
    ((i, s, o, g, r, a, m) => {
      i['GoogleAnalyticsObject'] = r
      i[r] = i[r] || function () { (i[r].q = i[r].q || []).push(arguments) }
      i[r].l = 1 * new Date()
      a = s.createElement(o)
      m = s.getElementsByTagName(o)[0]
      a.async = 1
      a.src = g
      m.parentNode.insertBefore(a, m)
    })(window, document, 'script', 'https://www.googletagmanager.com/gtag/js?id=UA-75421763-13', 'ga')
    window.dataLayer = window.dataLayer || []
    window.gtag = function () { window.dataLayer.push(arguments) }
    window.gtag('js', new Date())
  
    app.router.afterEach((to, from) => {
      // window.gtag('config', 'UA-75421763-13') // 安裝第一個 Google Analytics 與送出 PageView
      // window.gtag('config', 'UA-75421763-1') // 安裝第二個 Google Analytics 與送出 PageView
      // window.gtag('config', 'AW-858679249') // 安裝 Google Adwords
      // window.gtag('event', 'conversion', { 'send_to': 'AW-858679249/-STTCPaxg3sQ0c-5mQM' }) // 送出 Google Adwords 事件
    })
  }
  
new_contents: export default ({ app }) => {
    if (process.env.NODE_ENV !== 'production') { return false }
    ((i, s, o, g, r, a, m) => {
      i['GoogleAnalyticsObject'] = r
      i[r] = i[r] || function () { (i[r].q = i[r].q || []).push(arguments) }
      i[r].l = 1 * new Date()
      a = s.createElement(o)
      m = s.getElementsByTagName(o)[0]
      a.async = 1
      a.src = g
      m.parentNode.insertBefore(a, m)
    })(window, document, 'script', 'https://www.googletagmanager.com/gtag/js?id=UA-75421763-13', 'ga')
    window.dataLayer = window.dataLayer || []
    window.gtag = function () { window.dataLayer.push(arguments) }
    window.gtag('js', new Date())
  
    app.router.afterEach((to, from) => {
      // 因為網頁標題沒有更新的很即時，所以延遲一下發送
      // window.setTimeout(() => {
      //   window.gtag('config', 'UA-75421763-13', { 'page_title': window.document.title, 'page_path': to.path }) // 安裝第一個 Google Analytics 與送出 PageView
      //   window.gtag('config', 'UA-75421763-1', { 'page_title': window.document.title, 'page_path': to.path }) // 安裝第二個 Google Analytics 與送出 PageView
      // }, 512)
      // window.gtag('config', 'AW-858679249') // 安裝 Google Adwords
      // window.gtag('event', 'conversion', { 'send_to': 'AW-858679249/-STTCPaxg3sQ0c-5mQM' }) // 送出 Google Adwords 事件
    })
  }
  
subject: 修正 spa 傳送 ga 問題