Examine source code of Copy to Workflowy

{
  "manifest_version": 2,
  "name": "Copy to Workflowy",
  "version": "1.4",
  "description": "Copies the current tab's title and address so that it can be pasted into Workflowy.",
  "icons": {
    "48": "icons/workflowy-48.png"
  },
  "browser_action": {
    "default_icon": {
      "19": "icons/workflowy-19.png",
      "38": "icons/workflowy-38.png"
    },
    "default_title": "Copy to Workflowy"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "clipboardWrite",
    "notifications",
    "storage"
  ],
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+C"
      },
      "description": "Copy to Workflowy"
    }
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  }
}