Examine source code of CloseX

{
  "manifest_version": 2,
  "name": "CloseX",
  "version": "1.0.0",
  "description": "Automatically closes annoying popups and modals",
  "icons": {
    "16": "icons/closex-16.png",
    "32": "icons/closex-32.png",
    "64": "icons/closex-64.png",
    "128": "icons/closex-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.delfi.ee/*"
      ],
      "js": [
        "scripts/delfi.js"
      ]
    },
    {
      "matches": [
        "*://*.postimees.ee/*"
      ],
      "js": [
        "scripts/postimees.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{cea2e30d-c8fb-4c21-80f5-90651ad6b21a}"
    }
  }
}