Examine source code of Ask for Container

{
  "manifest_version": 2,
  "name": "Ask for Container",
  "version": "1.1.2",
  "description": "Prompts to select or create a container when opening external links",
  "author": "Finn",
  "permissions": [
    "contextualIdentities",
    "cookies",
    "tabs",
    "webNavigation",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_icon": {
      "48": "icons/icon-48.svg",
      "96": "icons/icon-96.svg"
    },
    "default_title": "Ask for Container",
    "default_popup": "popup/popup.html"
  },
  "icons": {
    "48": "icons/icon-48.svg",
    "96": "icons/icon-96.svg"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "ask-for-container@finn",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}