Examine source code of Mantis Helper

{
  "manifest_version": 2,
  "name": "Mantis Helper",
  "version": "1.2.0.0",
  "author": "Michael Fiedler",
  "permissions": [
    "contextMenus",
    "storage"
  ],
  "background": {
    "scripts": [
      "data/background.js"
    ]
  },
  "description": "Select a number on a website and open it in Mantis from the context menu",
  "options_ui": {
    "page": "data/options.html",
    "open_in_tab": true
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "64": "icons/icon64.png",
    "96": "icons/icon96.png",
    "128": "icons/icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "mantis-helper@monumental.at",
      "strict_min_version": "57.0"
    }
  }
}