Examine source code of Container Redirect

{
  "manifest_version": 2,
  "name": "Container Redirect",
  "version": "3.12.4",
  "description": "Firefox extension to automatically open websites in a container",
  "author": "Maxim Shpak <max.dw.i.git@outlook.com>",
  "homepage_url": "https://github.com/max-dw-i/container-redirect",
  "icons": {
    "48": "icons/icon.png",
    "96": "icons/icon.png"
  },
  "permissions": [
    "contextualIdentities",
    "cookies",
    "tabs",
    "webRequest",
    "webRequestBlocking",
    "storage",
    "<all_urls>"
  ],
  "browser_action": {
    "browser_style": true,
    "default_title": "Container Redirect",
    "default_popup": "ui/index.html",
    "default_icon": "icons/icon.png"
  },
  "background": {
    "scripts": [
      "index.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e70111b3-b362-47a7-bbdc-a6fb7249d47a}",
      "strict_min_version": "58.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "options_ui": {
    "page": "ui-preferences/index.html"
  }
}