Examine source code of BlockURL

{
  "manifest_version": 2,
  "name": "BlockURL",
  "version": "4.1.4",
  "description": "Blocks specific pages and URLs with the click of a button",
  "browser_specific_settings": {
    "gecko": {
      "id": "blockurl@beatlink.github.com",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "browsingActivity",
          "websiteContent"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "icons": {
    "48": "no.png"
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "storage",
    "tabs",
    "activeTab",
    "menus",
    "alarms",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module",
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "contentScript.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": {
      "48": "no.png"
    }
  },
  "page_action": {
    "default_icon": "no.png",
    "default_title": "Toggle Blocking for this Page",
    "show_matches": [
      "<all_urls>"
    ]
  },
  "options_ui": {
    "page": "/options/options.html"
  }
}