app/bundles/PluginBundle/Resources/views/Auth/auth.html.twig

{% set contentOnly = true %}
{% extends '@MauticCore/Default/content.html.twig' %}

{% block headerTitle '' %}

{% block content %}
  {{- assetAddScriptDeclaration('Mautic.handleIntegrationCallback("'~integration~'", "'~csrfToken~'", "'~code~'", "'~callbackUrl~'", "'~clientIdKey~'", "'~clientSecretKey~'");', 'bodyClose') -}}
{% endblock %}