Examine source code of Split-Online

{
  "manifest_version": 2,
  "name": "Split-Online",
  "description": "Split-Online - Brondata extensie.",
  "version": "2.1.0",
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "homepage_url": "https://split-online.nl/",
  "applications": {
    "gecko": {
      "id": "aqopi@split-online-v2.nl",
      "strict_min_version": "60.0"
    }
  },
  "icons": {
    "32": "resources/logo32X32.png",
    "48": "resources/logo48X48.png",
    "128": "resources/logo128X128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://iwize.nl/generic/*",
        "https://*.aqopi.com/*",
        "https://*.overheid.nl/*",
        "https://*.mijnpensioenoverzicht.nl/*",
        "https://*.uwv.nl/*",
        "https://*.belastingdienst.nl/*",
        "https://*.duo.nl/*",
        "https://*.digid.nl/*"
      ],
      "run_at": "document_start",
      "js": [
        "content/content.js",
        "content/actions.js",
        "content/crypto.js",
        "content/templateMatching.js",
        "content/fetchBlob.js",
        "content/downloadPdfByClick.js",
        "content/fetchJson.js"
      ]
    },
    {
      "matches": [
        "https://*.overheid.nl/*"
      ],
      "run_at": "document_start",
      "js": [
        "content/interceptMoh.js"
      ]
    },
    {
      "matches": [
        "https://mijn.duo.nl/*"
      ],
      "run_at": "document_start",
      "js": [
        "content/fetchJsonWithAuthHeader.js"
      ]
    },
    {
      "all_frames": true,
      "matches": [
        "https://iwize.nl/*",
        "https://*.split-online.nl/*"
      ],
      "run_at": "document_start",
      "js": [
        "content/requestor-content.js"
      ]
    }
  ],
  "permissions": [
    "tabs",
    "activeTab",
    "cookies",
    "webRequest",
    "webNavigation",
    "https://*.aqopi.com/*",
    "https://iwize.nl/*",
    "https://*.split-online.nl/*",
    "https://*.overheid.nl/*",
    "https://*.mijnpensioenoverzicht.nl/*",
    "https://*.uwv.nl/*",
    "https://*.belastingdienst.nl/*",
    "https://*.duo.nl/*",
    "https://*.digid.nl/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "resources/logo32X32.png",
    "default_title": "Split-Online"
  },
  "web_accessible_resources": [
    "resources/logo80X80.png"
  ]
}