Examine source code of HTTP Header Plugin

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "version": "1.0.1",
  "description": "__MSG_extensionDescription__",
  "browser_specific_settings": {
    "gecko": {
      "id": "http-header-plugin@paulpepper.com",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png",
    "128": "icons/icon-128.png"
  },
  "browser_action": {
    "default_icon": "icons/icon-48.png",
    "default_title": "__MSG_extensionName__"
  },
  "options_ui": {
    "page": "options/options.html",
    "browser_style": true
  },
  "background": {
    "scripts": [
      "background/urlMatching.js",
      "background/index.js"
    ]
  },
  "permissions": [
    "storage",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "default_locale": "en"
}