pdfjs - Displaying a document

Question

I am trying to display all PDF stored on a folder. I have the following code that throws no error besides "Warning: TT: undefined function: 32 on util.js:373". In the DevTools I can see that the PDF document is found and loaded, and actualy the full website seems to be working fine, but a blank screen is showed on the brower where the PDF should be loaded.

The site loads first showPDF() function.

This is the showPDF() function:

    function showPDFs() {
        webFrame.src = 'about:blank';
        pdfContainer.style.display = 'block';

        // Obtener la lista de archivos PDF mediante AJAX
        const xhr = new XMLHttpRequest();
        xhr.onreadystatechange = function () {
            if (xhr.readyState === 4 && xhr.status === 200) {
                const pdfList = JSON.parse(xhr.responseText);
                displayPDFs(pdfList, 0);
            }
        };
        xhr.open('GET', 'get_pdf_list.php', true);
        xhr.send();
    }

and displayPDF() function:

    function displayPDFs(pdfList, index) {
        if (index >= pdfList.length) {
            setTimeout(showWeb, pdfDisplayTime);
            return;
        }

        const pdfUrl = pdfList[index];

        // Cargar y mostrar el PDF en el visor de PDF.js
        pdfContainer.innerHTML = '<canvas id="pdf-canvas"></canvas>';

        const canvas = document.getElementById('pdf-canvas');

        pdfjsLib.getDocument({ url: pdfUrl }).promise.then(function (pdfDoc) {
            pdfDoc.getPage(1).then(function (page) {
                const viewport = page.getViewport({ scale: 1.5 });
                canvas.height = viewport.height;
                canvas.width = viewport.width;

                const context = canvas.getContext('2d');

                page.render({
                    canvasContext: context,
                    viewport: viewport
                }).promise.then(function () {
                    setTimeout(() => {
                        displayPDFs(pdfList, index + 1);
                    }, pdfDisplayTime);
                });
            });
        });
    }

This is the get_pdf_list.php code:

<?php
$dir = 'files/BRKROOM01/';
$files = array_diff(scandir($dir), array('..', '.'));

$pdfList = [];
foreach ($files as $file) {
    if (pathinfo($file, PATHINFO_EXTENSION) == 'pdf') {
        $pdfList[] = $dir . $file;
    }
}

echo json_encode($pdfList);
?>

I can't see anything wrong, and as mentioned, everything seems to be running but no PDF displayed. I tried changing the code a thousand times, but nothing works.