Chrome扩展程序：响应storage.get时出错：TypeError

Question

运行chrome扩展程序时出现错误：

Error in response to storage.get: TypeError: Cannot read property 'innerHTML' of undefined

Context
popup.html
Stack Trace
script.js:324 (temp.map)
script.js:324 (Object.chrome.storage.local.get [as callback])
jquery/jquery-3.2.1.min.js:2 (i)
jquery/jquery-3.2.1.min.js:2 (Object.fireWith [as resolveWith])

第

行的代码

324：var messageTest = temp.map((x, i) => "message =" + x[0].innerHTML + ", time= " + x[2].innerHTML + ((i % 2 === 0) ? "message by user" : " message by s"));