Examine source code of Gcontacts Sidebar

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "version": "1.0",
  "default_locale": "en",
  "homepage_url": "https://linktr.ee/jusore",
  "browser_specific_settings": {
    "gecko": {
      "id": "{fb1e4103-88ec-4ed6-a694-56d7201103a3}",
      "strict_min_version": "73.0"
    }
  },
  "chrome_settings_overrides": {
    "search_provider": {
      "name": "Gmailto",
      "search_url": "https://mail.google.com/mail/u/0/?fs=1&tf=cm&source=mailto&su={searchTerms}",
      "keyword": "@gmailto",
      "favicon_url": "icons/gmto_icon512.svg",
      "is_default": false,
      "encoding": "UTF-8"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "512": "icons/gc_icon512.svg"
  },
  "options_ui": {
    "page": "options/options.html",
    "browser_style": true
  },
  "sidebar_action": {
    "default_icon": {
      "512": "icons/gc_icon512.svg"
    },
    "default_title": "__MSG_extensionName__",
    "browser_style": false,
    "default_panel": "index.html"
  },
  "browser_action": {
    "default_icon": {
      "512": "icons/gc_icon512.svg"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://contacts.google.com/*"
      ],
      "css": [
        "css/styles.css"
      ],
      "run_at": "document_start"
    }
  ],
  "permissions": [
    "storage",
    "*://contacts.google.com/*"
  ],
  "commands": {
    "_execute_sidebar_action": {
      "suggested_key": {
        "default": "Ctrl+Alt+C"
      }
    }
  }
}