Examine source code of Cabinet

{
  "manifest_version": 3,
  "name": "Cabinet",
  "version": "0.0.1",
  "description": "Manages your Firefox tabs",
  "icons": {
    "48": "icons/cabinet.svg",
    "96": "icons/cabinet.svg"
  },
  "action": {
    "default_icon": "icons/cabinet.svg",
    "default_title": "Organise tabs"
  },
  "permissions": [
    "tabs"
  ],
  "background": {
    "scripts": [
      "background/cabinet.js"
    ],
    "type": "module"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "addon@alexghr.me",
      "strict_min_version": "112.0"
    }
  }
}