External Followed Link Highlighter

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "External Followed Link Highlighter",
  "short_name": "Link Highlighter",
  "description": "Checks all links on a page for any external links that do not have the attribute rel=\"nofollow\" and highlights them in a red border.",
  "version": "1.2",
  "author": "Richard Parnaby-King",
  "homepage_url": "https://github.com/richard-parnaby-king/External-Followed-Link-Highlighter",
  "icons": {
    "128": "icon.png"
  },
  "options_page": "options/options.html",
  "browser_action": {
    "default_icon": "icon.png"
  },
  "permissions": [
    "tabs",
    "storage",
    "http://*/*",
    "https://*/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  }
}