Examine source code of Syncboard

{
  "icons": {
    "16": "icon16.plasmo.6c567d50.png",
    "32": "icon32.plasmo.76b92899.png",
    "48": "icon48.plasmo.aced7582.png",
    "64": "icon64.plasmo.8bb5e6e0.png",
    "128": "icon128.plasmo.3c1ed2d2.png"
  },
  "manifest_version": 2,
  "browser_action": {
    "default_icon": {
      "16": "icon16.plasmo.6c567d50.png",
      "32": "icon32.plasmo.76b92899.png",
      "48": "icon48.plasmo.aced7582.png",
      "64": "icon64.plasmo.8bb5e6e0.png",
      "128": "icon128.plasmo.3c1ed2d2.png"
    },
    "default_popup": "popup.html"
  },
  "version": "0.1.9",
  "author": "Adib Zaini",
  "name": "Syncboard",
  "description": "Copy and paste from different devices without extra steps",
  "background": {
    "scripts": [
      "static/background/index.js"
    ],
    "persistent": true
  },
  "permissions": [
    "storage",
    "notifications",
    "alarms",
    "clipboardWrite",
    "http://*/*",
    "https://*/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.883ade9e.js"
      ],
      "css": [],
      "run_at": "document_end"
    }
  ],
  "web_accessible_resources": [
    "icon16.plasmo.6c567d50.png",
    "icon32.plasmo.76b92899.png",
    "icon48.plasmo.aced7582.png",
    "icon64.plasmo.8bb5e6e0.png",
    "icon128.plasmo.3c1ed2d2.png",
    "popup.html",
    "static/background/index.js",
    "content.883ade9e.js",
    "offscreen.601b9a01.html",
    "offscreen.981262d7.js"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{09075a70-8b12-4c59-85e7-545a6b2bccc6}"
    }
  }
}