Examine source code of Webpage Color Changer

{
  "manifest_version": 2,
  "name": "Webpage Color Changer",
  "version": "1.0",
  "description": "Change the background color of the current webpage.",
  "icons": {
    "48": "icons/color-change-icon-48.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/color-change-icon-48.png",
    "default_popup": "color-picker.html",
    "default_title": "Change Color"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content-script.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{86896f01-e950-4524-8127-92197dd1264a}"
    }
  }
}