Examine source code of AskBlocker

{
  "manifest_version": 2,
  "name": "AskBlocker",
  "description": "Blocks overly-eager permission requests for notifications, location, etc. For example, before you've interacted with the page.",
  "version": "1.0.8resigned1",
  "homepage_url": "https://adamlynch.com/askblocker",
  "background": {
    "scripts": [
      "browser-polyfill.min.js",
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "icons/askBlocker-128.png",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "all_frames": true,
      "js": [
        "browser-polyfill.min.js",
        "content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "icons": {
    "16": "icons/askBlocker-16.png",
    "32": "icons/askBlocker-32.png",
    "48": "icons/askBlocker-48.png",
    "128": "icons/askBlocker-128.png",
    "512": "icons/askBlocker-512.png"
  },
  "permissions": [],
  "browser_specific_settings": {
    "gecko": {
      "id": "{9c73fba1-918c-406e-aff1-6eb9a9084cab}"
    }
  }
}