Examine source code of HTML/CSS Live Injector

{
  "manifest_version": 2,
  "name": "HTML/CSS Live Injector",
  "version": "1.0",
  "description": "Inject HTML and CSS code into the current page.",
  "permissions": [
    "activeTab",
    "tabs"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png",
    "default_title": "Inject HTML/CSS"
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{27f47998-495f-40ce-b5e4-f4a7a15c8b31}"
    }
  }
}