Examine source code of Calofree

{
  "manifest_version": 2,
  "name": "Calofree",
  "version": "1.0.2",
  "description": "Hides calorie information on websites",
  "permissions": [
    "storage"
  ],
  "icons": {
    "48": "icons/calofree-48.png",
    "128": "icons/calofree-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "dist/calofree.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": "icons/calofree-48.png",
    "default_title": "Calofree",
    "default_popup": "src/calofree.html"
  },
  "options_ui": {
    "page": "src/calofree.html",
    "browser_style": false,
    "chrome_style": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{b949930c-119a-47b8-a824-853015e956e2}"
    }
  }
}