Examine source code of Spotlight

{
  "manifest_version": 2,
  "version": "2.0.19",
  "name": "Spotlight",
  "description": "Reduce your digital distractions",
  "icons": {
    "16": "icon16.png",
    "32": "icon32.png",
    "128": "icon128.png"
  },
  "background": {
    "scripts": [
      "event.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_title": "Spotlight",
    "default_popup": "popup.html"
  },
  "permissions": [
    "storage",
    "contextMenus",
    "tabs",
    "<all_urls>"
  ],
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "css": [],
      "js": [
        "content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "web_accessible_resources": [
    "moz-extension://d6d001b5-1ba8-c34e-bf86-cd013309eda4/signin.html"
  ]
}