Examine source code of Blockella

{
  "manifest_version": 2,
  "name": "Blockella",
  "version": "1.4",
  "description": "Block influencers on index.hr news portal",
  "icons": {
    "64": "icons/not-allowed.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.index.hr/*"
      ],
      "js": [
        "blockella.js"
      ]
    }
  ]
}