Examine source code of Smart TOC

{
  "manifest_version": 3,
  "name": "Smart TOC",
  "version": "0.13.2",
  "description": "Webpage outliner",
  "action": {
    "default_icon": "icons/icon.png",
    "default_title": "Toggle table of contents"
  },
  "icons": {
    "128": "icons/icon.png"
  },
  "background": {
    "scripts": [
      "background/index.js"
    ]
  },
  "commands": {
    "toggle": {
      "description": "Show/hide TOC"
    },
    "prev": {
      "description": "Jump: to previous heading"
    },
    "next": {
      "description": "Jump: to next heading"
    },
    "search": {
      "description": "Search: toggle (Pro)"
    },
    "theme": {
      "description": "Theme: toggle dark mode (Pro)"
    },
    "expand:more": {
      "description": "Expand: more"
    },
    "expand:less": {
      "description": "Expand: less"
    },
    "expand:auto": {
      "description": "Expand: auto"
    },
    "side:left": {
      "description": "Panel side: left"
    },
    "side:right": {
      "description": "Panel side: right"
    },
    "side:toggle": {
      "description": "Panel side: toggle"
    },
    "display:sidePanel": {
      "description": "Display: as side panel"
    },
    "display:floating": {
      "description": "Display: as floating"
    },
    "display:toggle": {
      "description": "Display: toggle"
    }
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "permissions": [
    "activeTab",
    "scripting",
    "storage"
  ],
  "optional_permissions": [
    "tabs",
    "*://*/*",
    "file:///*"
  ],
  "optional_host_permissions": [
    "*://*/*",
    "file:///*"
  ],
  "author": "FallenMax@gmail.com",
  "browser_specific_settings": {
    "gecko": {
      "id": "{40289693-01fe-4740-91ae-07344bf5b09b}",
      "strict_min_version": "58.0"
    }
  }
}