Chrome扩展程序：如何从background.js自动填写表单后捕获弹出消息？

Question

我正在创建一个chrome扩展程序-它会自动多次填充某个Web表单。 Background.js将消息发送到content.js，效果很好。提交表单后，网站弹出一条消息，例如“表单已提交。参考号为...”，我想捕获所有这些消息。如何实现呢？

background.js

window.popups = []
chrome.runtime.onMessage.addListener(
  function(request, sender, sendResponse) {
    if (request.type === "myType") {
        chrome.tabs.create({
            url: "https://www.example.com/form"
        }, function(tab) {
          chrome.tabs.onUpdated.addListener(function listener(tabId, changeInfo) {
            if (tabId === tab.id && changeInfo.status == 'complete') {
              chrome.tabs.onUpdated.removeListener(listener)
              chrome.tabs.sendMessage(tabId, {"msg":"hello"}, function(res){})
            }
          })
        })
      }else if(request.type === "popup"){
        const msg = request.msg
        window.popups.push(msg)
      }
  }

我想在提交每个表单后调用此getPopup函数。

function getPopup(){
        chrome.tabs.query({currentWindow: true, active: true},
            function(tabs){
                chrome.tabs.sendMessage(tabs[0].id, {'type':'submitted'}, readPopupArr)
            }
        )
    }

content.js

chrome.runtime.onMessage.addListener(function(request, sender, sendResponse) {
    if(request.something){

    }else if(request.type == "submitted"){
        let msg = $(".someclass").text()
                msg = msg.replace("OK", "");
chrome.runtime.sendMessage({
          type:"popup", msg:msg
        })
    }

})