jellyfin/MediaBrowser.WebDashboard/Html/scripts/WizardFinishPage.js

var WizardFinishPage = {
  
    onFinish: function() {
        
        ApiClient.getServerConfiguration().done(function (config) {

            config.IsStartupWizardCompleted = true;

            ApiClient.updateServerConfiguration(config).done(function() {
                Dashboard.navigate('dashboard.html');
            });
        });

    }

};