Examine source code of Atlas

{
  "name": "Atlas",
  "version": "1.2.2",
  "description": "Organise knowledge-rich-content from around the internet.",
  "icons": {
    "16": "img/favicon-16x16-browser.png",
    "32": "img/favicon-32x32-browser.png",
    "96": "img/favicon-96x96-browser.png"
  },
  "browser_action": {
    "default_icon": {
      "16": "img/favicon-16x16-browser.png",
      "32": "img/favicon-32x32-browser.png",
      "96": "img/favicon-96x96-browser.png"
    },
    "default_title": "Add to Atlas"
  },
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "css": [
        "css/main.css"
      ],
      "js": [
        "js/inject.js"
      ]
    },
    {
      "matches": [
        "*://*.twitter.com/*",
        "*://twitter.com/*"
      ],
      "css": [
        "css/twitter/twitter.css"
      ],
      "js": [
        "js/twitter/twitter.js"
      ]
    }
  ],
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "windows": "Ctrl+Shift+A",
        "mac": "Command+Shift+A",
        "chromeos": "Ctrl+Shift+A",
        "linux": "Ctrl+Shift+A"
      },
      "description": "Add to Atlas"
    }
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "web_accessible_resources": [
    "img/*"
  ],
  "manifest_version": 2,
  "browser_specific_settings": {
    "gecko": {
      "id": "team@editmode.com",
      "strict_min_version": "42.0"
    }
  }
}