Examine source code of RJump

{
  "manifest_version": 2,
  "name": "RJump",
  "description": "RJ코드를 드래그로 선택하면 dlsite 검색할 수 있는 도구",
  "version": "1.0.1",
  "icons": {
    "32": "icons/icon.png"
  },
  "background": {
    "scripts": [
      "background_script.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://gall.dcinside.com/*"
      ],
      "js": [
        "contentScripts/readSelect.js"
      ]
    }
  ],
  "permissions": [
    "contextMenus"
  ]
}