Examine source code of Unicode Character Picker

{
  "manifest_version": 3,
  "name": "Unicode Character Picker",
  "version": "0.1.0",
  "description": "A quick and easy way to find and insert special Unicode characters.",
  "browser_specific_settings": {
    "gecko": {
      "id": "unicode-character-picker@melker.dev"
    }
  },
  "icons": {
    "48": "icons/icon-48.png"
  },
  "action": {
    "default_icon": "icons/icon-48.png",
    "default_title": "Unicode Picker"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "css": [
        "style.css"
      ],
      "js": [
        "characters.js",
        "content.js"
      ]
    }
  ],
  "commands": {
    "toggle-picker": {
      "suggested_key": {
        "default": "Ctrl+Space",
        "mac": "Command+Space"
      },
      "description": "Open Unicode Character Picker"
    }
  },
  "permissions": [
    "activeTab",
    "scripting",
    "storage"
  ]
}