Examine source code of Syncfy

{
  "name": "Syncfy",
  "description": "Syncfy extension used to complement connections",
  "version": "1.0.0",
  "manifest_version": 2,
  "author": "Luis Saúl González Guerra",
  "icons": {
    "16": "/assets/icons/16.png",
    "32": "/assets/icons/32.png",
    "48": "/assets/icons/48.png",
    "128": "/assets/icons/128.png"
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1ac5d4a6-b00e-4d79-bfcc-ed3467b14e91}"
    }
  }
}