Examine source code of 128-Byte Text Pouch

{
  "manifest_version": 2,
  "name": "128-Byte Text Pouch",
  "version": "1.4",
  "description": "A simple addon to copy text/store a custom string of a maximum of 32 characters/128-Byte. Flash disk icons created by DinosoftLabs - https://www.flaticon.com/free-icons/flash-disk",
  "permissions": [
    "storage",
    "clipboardWrite"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "128-Byte Text Pouch",
    "default_icon": {
      "16": "floppy-disk.png",
      "32": "floppy-disk.png",
      "48": "floppy-disk.png",
      "128": "floppy-disk.png"
    }
  },
  "icons": {
    "16": "floppy-disk.png",
    "32": "floppy-disk.png",
    "48": "floppy-disk.png",
    "128": "floppy-disk.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{691d7f84-79ef-4124-aaf6-d256c8009ff3}"
    }
  }
}