How we work

Prefer && over ?

Let's start with code.

1{lessonIds && lessonIds[lessonIds.length - 1] != lesson.id ? (
2  <Button
3    className="mx-2"
4    label="Next"
5    onClick={() => handleNextButton(lesson.id)}
6   />
7) : null}

In the above case we can use && and that would make code more readable and we do not have to worry about returning a null.

1{lessonIds && lessonIds[lessonIds.length - 1] != lesson.id && (
2  <Button
3    className="mx-2"
4    label="Next"
5    onClick={() => handleNextButton(lesson.id)}
6   />
7)}