Examine source code of simple-header-changer

{
  "description": "simple header changer setting in json ",
  "manifest_version": 2,
  "name": "simple-header-changer",
  "version": "1.2resigned1",
  "permissions": [
    "<all_urls>",
    "webRequestBlocking",
    "webRequest",
    "storage",
    "contextMenus"
  ],
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "applications": {
    "gecko": {
      "id": "shc@paco.jp",
      "strict_min_version": "57.0a1"
    }
  },
  "icons": {
    "48": "icons/48.png",
    "96": "icons/96.png"
  }
}