Examine source code of New Easy Reader

{
  "browser_specific_settings": {
    "gecko": {
      "id": "aqsak8411@gmail.com"
    }
  },
  "manifest_version": 2,
  "name": "New Easy Reader",
  "version": "1.4.1",
  "description": "Modify a web page to make it easily readable",
  "icons": {
    "48": "/icons/smartReader-48.png"
  },
  "permissions": [
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "/content_scripts/assembleWantedElements.js",
        "/content_scripts/filterElements.js",
        "/content_scripts/isThisTag.js",
        "/content_scripts/modifyHtml.js",
        "/content_scripts/removeBold.js",
        "/content_scripts/textAtRoot.js",
        "/content_scripts/isAddonActived.js",
        "/content_scripts/isItLetter.js",
        "/content_scripts/updatePage.js",
        "main.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "/background/changeMode.js",
      "/background/handleMessage.js",
      "/background/updateIcon.js",
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "16": "/icons/button/smartReader-white-16.png",
      "32": "/icons/button/smartReader-white-32.png"
    },
    "default_title": "Smart Reader settings",
    "theme_icons": [
      {
        "light": "/icons/button/smartReader-white-16.png",
        "dark": "/icons/button/smartReader-black-16.png",
        "size": 16
      },
      {
        "light": "/icons/button/smartReader-white-32.png",
        "dark": "/icons/button/smartReader-black-32.png",
        "size": 32
      }
    ],
    "default_popup": "/popup/smartReader_popup.html"
  }
}