Examine source code of Virgool Liker

{
  "manifest_version": 2,
  "name": "Virgool Liker",
  "version": "4.0",
  "description": "Lets Like Virgool Post Without Any Limitation",
  "icons": {
    "48": "like.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://virgool.io/*"
      ],
      "js": [
        "script.js"
      ]
    }
  ]
}