Greasy Fork

Level display

I would suggest to show each level for vocabulary word on separate lines. I changed the display procedure to

      let sublist = document.createElement('ul');
        innerContainer.appendChild(sublist);
        this.vocabulary.forEach((word) => {
          if (word.isMarker) {
            sublist = document.createElement('ul');
            innerContainer.appendChild(sublist);
          }
          let wordElement = new WordElement(word);
          wordElement.attachTo(sublist);
      });

This makes looking at different level easier

Updated