如何在Chrome扩展程序中导入html2canvas

我使用以下代码创建了一个扩展来捕获正文,但我收到了一条错误消息。

请帮忙。

[错误消息]

Uncaught (in promise) TypeError: Failed to fetch dynamically imported module: chrome-extension://... /js/content.js

[源代码] manifest.json

  "content_scripts": [
    {
        "matches": ["<all_urls>"],
        "js": [ "script.js" ]
    }
  ],
  "web_accessible_resources": [
    {
      "matches": ["<all_urls>"],
      "resources": [
          "js/content.js",
          "js/html2canvas.js"
      ]
    }
  ]

content.js

import html2canvas from './html2canvas';

let target_element = document.getElementsByTagName('body')[0];
let button_element = document.createElement('button');
button_element.setAttribute("id", "captcha-btn");
button_element.innerHTML = 'test';
target_element.prepend(button_element);

let target_pankuzu_element = document.getElementsByTagName('body')[0];
let img_element = document.createElement('img');
img_element.setAttribute("id", "result");
target_pankuzu_element.prepend(img_element);

const BUTTON_CLICK_EVENT= document.getElementById('captcha-btn');
BUTTON_CLICK_EVENT.addEventListener('click', () => {
    html2canvas(document.getElementsByTagName('body')[0],{}).then(function(canvas){
        document.getElementById('result').src = canvas.toDataURL();
    })
});

script.js

(async() => {
    const src = chrome.runtime.getURL("js/content.js");
    const contentMain = await import(src);
})();

无错误地执行。