Examine source code of Purewall

{
  "manifest_version": 2,
  "name": "Purewall",
  "version": "2.9.0",
  "description": "Block ads, trackers and malware. Pure web experience — powered by EasyList, AdGuard & uBlock filters.",
  "permissions": [
    "declarativeNetRequest",
    "declarativeNetRequestWithHostAccess",
    "declarativeNetRequestFeedback",
    "storage",
    "tabs",
    "activeTab",
    "alarms",
    "webNavigation",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "declarative_net_request": {
    "rule_resources": [
      {
        "id": "ad_rules",
        "enabled": true,
        "path": "rules/ad_rules.json"
      },
      {
        "id": "tracker_rules",
        "enabled": true,
        "path": "rules/tracker_rules.json"
      },
      {
        "id": "custom_rules",
        "enabled": true,
        "path": "rules/custom_rules.json"
      }
    ]
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "purewall@hasi-elektronic.de",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  }
}