 keyboard open (for debugging)
      // window.mathVirtualKeyboard.addEventListener(
      //   'before-virtual-keyboard-toggle',
      //   (ev) => {
      //     if (virtualKeyboard.visible) ev.preventDefault();
      //   }
      // );

      window.mathVirtualKeyboard.addEventListener('geometrychange', (ev) => {
        const kbdPanel = document.getElementById('keyboard-container');
        kbdPanel.style.height = `${mathVirtualKeyboard.boundingRect.height}px`;
      });

      document.addEventListener