Examine source code of Search with Variables

{
  "name": "__MSG_extName__",
  "description": "__MSG_extDescription__",
  "version": "1.0.0",
  "manifest_version": 2,
  "default_locale": "en",
  "permissions": [
    "storage",
    "notifications"
  ],
  "background": {
    "scripts": [
      "browser-polyfill.min.js",
      "shared.js",
      "background.js"
    ],
    "persistent": false
  },
  "omnibox": {
    "keyword": "!"
  },
  "browser_action": {
    "default_icon": {
      "16": "icon16.png",
      "32": "icon32.png"
    },
    "default_popup": "popup.html"
  },
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+L"
      }
    }
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "icons": {
    "16": "icon16.png",
    "32": "icon32.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4397b935-aae4-4b2c-8afe-6655491dee56}",
      "strict_min_version": "42.0"
    },
    "edge": {
      "browser_action_next_to_addressbar": true
    }
  }
}