List.contains('dark') ? 'dark' : 'light',
                  // Use language-agnostic URL
                  previewRender: function(plainText) {
                      // Create a temporary form
                      const formData = new FormData();
                      formData.append('content', plainText);

                      // Use a synchronous request to get the rendered HTML
                      const xhr = new XMLHttpRequest();
                      xhr.open('POST', '{% url "markdownx_markdownify"