Examine source code of Tig

{
  "manifest_version": 2,
  "name": "Tig",
  "version": "1.0",
  "description": "Allow you to tag pages with a color and text. Useful for tagging articles/documentation as read/understood, for revision by tagging articles as 'Mastered', 'In Progress', and 'Need Help'",
  "homepage_url": "https://github.com/sysfig/tig",
  "icons": {
    "48": "icons/default_48.png",
    "96": "icons/default_96.png"
  },
  "permissions": [
    "activeTab",
    "storage",
    "tabs",
    "unlimitedStorage"
  ],
  "browser_action": {
    "default_icon": "icons/default_96.png",
    "default_title": "Tag Page",
    "default_popup": "popup/index.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}