Examine source code of COOABIT

{
  "browser_specific_settings": {
    "gecko": {
      "id": "cooabit@gmail.com",
      "strict_min_version": "42.0"
    }
  },
  "background": {
    "scripts": [
      "background/background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "19": "icons/logomini.png",
      "38": "icons/32x32.png"
    },
    "default_title": "COOABIT",
    "default_popup": "index.html"
  },
  "commands": {
    "toggle-feature": {
      "suggested_key": {
        "default": "Ctrl+Shift+Y",
        "linux": "Ctrl+Shift+U"
      },
      "description": "Send a 'toggle-feature' event"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "jq/jquery-3.1.0.min.js",
        "jq/inject.js"
      ]
    }
  ],
  "description": "https://cooabit.com",
  "icons": {
    "48": "icons/48x48.png",
    "96": "icons/128x128.png"
  },
  "manifest_version": 2,
  "name": "COOABIT",
  "page_action": {
    "default_icon": {
      "19": "icons/16x16.png",
      "38": "icons/32x32.png"
    },
    "default_title": "COOABIT"
  },
  "permissions": [
    "tabs",
    "cookies",
    "<all_urls>",
    "storage"
  ],
  "version": "0.2",
  "web_accessible_resources": [
    "*"
  ]
}