Examine source code of Password Displayer

{
  "manifest_version": 2,
  "name": "Password Displayer",
  "version": "1.0",
  "description": "Adds an option to look at passwords in inputs boxes",
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "main.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "contextMenus"
  ]
}