Examine source code of Multi-tab

{
  "$schema": "https://json.schemastore.org/webextension.json",
  "manifest_version": 2,
  "name": "Multi-tab",
  "description": "A browser extension to open and group a bunch of tabs from a list of URLs.",
  "homepage_url": "https://github.com/LukeCarrier/multi-tab",
  "developer": {
    "name": "Luke Carrier",
    "url": "https://luke.carrier.im"
  },
  "version": "0.3.0",
  "permissions": [
    "tabs"
  ],
  "default_locale": "en",
  "browser_action": {
    "browser_style": true,
    "default_title": "Multi-tab",
    "default_popup": "popup/index.html",
    "default_icon": {
      "16": "icons/logo-16.png",
      "19": "icons/logo-19.png",
      "32": "icons/logo-32.png",
      "38": "icons/logo-38.png"
    }
  },
  "icons": {
    "48": "icons/logo-48.png",
    "96": "icons/logo-96.png",
    "128": "icons/logo-128.png",
    "256": "icons/logo-256.png",
    "512": "icons/logo-512.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{47dab1ed-f523-4eb3-8689-710e68723279}"
    }
  }
}