Examine source code of Flash Debugger

{
  "manifest_version": 2,
  "name": "Flash Debugger",
  "version": "6.0.8",
  "description": "Flash Debugging Evolved",
  "author": "O-Minds",
  "icons": {
    "48": "icon.png",
    "96": "icon.png"
  },
  "background": {
    "scripts": [
      "/libs/jquery-3.2.1.min.js",
      "/libs/swfWorker.js",
      "/libs/decompiler.js",
      "background.js"
    ]
  },
  "devtools_page": "index.html",
  "options_ui": {
    "page": "/settings/settings.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "run_at": "document_start",
      "all_frames": true,
      "js": [
        "/libs/mutation.js",
        "/libs/outbound.js",
        "/libs/portal.js"
      ]
    }
  ],
  "applications": {
    "gecko": {
      "id": "@flash_debugger"
    }
  },
  "content_security_policy": "script-src 'self'; object-src 'self';",
  "permissions": [
    "webRequest",
    "activeTab",
    "browserSettings",
    "tabs",
    "theme",
    "storage",
    "nativeMessaging",
    "<all_urls>"
  ]
}