Examine source code of open-in-reader-mode

{
  "manifest_version": 2,
  "name": "open-in-reader-mode",
  "version": "1.1resigned1",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "contextMenus",
    "activeTab"
  ],
  "icons": {
    "48": "icons/page-481.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{7af009bd-61c1-4aa7-a3e9-66420816be60}"
    }
  }
}