Examine source code of Board Keeper

{
  "name": "board-keeper",
  "version": "1.4.2",
  "manifest_version": 2,
  "description": "A chrome extension to keep your visited boards of Mural. Miro, Conceptboard are on the Roadmap..",
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "default_title": "board keeper",
    "default_popup": "popup.html",
    "default_icon": "icon-34.png"
  },
  "icons": {
    "16": "icon-16.png",
    "32": "icon-32.png",
    "34": "icon-34.png",
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://app.mural.co/*",
        "*://miro.com/*",
        "*://app.conceptboard.com/*"
      ],
      "js": [
        "contentScript.bundle.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "icon-128.png",
    "icon-34.png"
  ],
  "content_security_policy": "script-src 'self' 'unsafe-eval'; object-src 'self'",
  "browser_specific_settings": {
    "gecko": {
      "id": "{d88589f4-f16e-42c6-8b0f-82f00bd17814}"
    }
  }
}