Examine source code of History Cleaner

{
  "manifest_version": 2,
  "name": "History Cleaner",
  "version": "3.1",
  "description": "Press a hotkey to delete blacklisted sites from browser history.",
  "permissions": [
    "history",
    "storage",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "historycleaner-lknq@local.dev",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "History Cleaner",
    "default_icon": {
      "48": "icon.png"
    }
  },
  "icons": {
    "48": "icon.png"
  },
  "commands": {
    "clean-history": {
      "suggested_key": {
        "default": "Alt+Shift+X"
      },
      "description": "Clear blacklisted/whitelisted sites from history"
    },
    "open-settings": {
      "suggested_key": {
        "default": "Alt+Shift+Z"
      },
      "description": "Open History Cleaner settings"
    }
  }
}