Have you ever thought about adding meta tag to blade element?

<meta name="csrf-token" content="{{ csrf_token() }}">

function pollActiveEvent() {
    var locale = localStorage.getItem('selectedLanguage') || 'default_locale';
    var csrfToken = $('meta[name="csrf-token"]').attr('content');

    $.ajax({
        url: '/get-active-event-translations',
        type: 'GET',
        headers: { 'X-CSRF-TOKEN': csrfToken },
        data: { locale: locale },
        success: function(response) {
            updateActiveEvent(response);
            setTimeout(pollActiveEvent, 5000);
        },
        error: function() {
            console.error("Failed to request active event.");
            setTimeout(pollActiveEvent, 5000);
        }
    });
}

pollActiveEvent();