Examine source code of syncmarx (alpha)

{
  "manifest_version": 3,
  "name": "syncmarx",
  "version": "0.9.2",
  "author": "Greg McLeod",
  "description": "Web extension built for cross-browser bookmark syncing to the cloud.",
  "icons": {
    "48": "icons/icon_48.png",
    "96": "icons/icon_96.png"
  },
  "permissions": [
    "bookmarks",
    "storage",
    "alarms"
  ],
  "host_permissions": [
    "https://*.dropboxapi.com/",
    "https://*.google.com/",
    "https://*.googleapis.com/",
    "https://*.box.com/"
  ],
  "action": {
    "default_icon": "icons/icon_38.png",
    "default_title": "syncmarx (alpha)",
    "default_popup": "settings.htm"
  },
  "background": {
    "scripts": [
      "app.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{15b7a1ef-fbc2-41de-ba8e-502b1b79b8fd}"
    }
  }
}