findActiveDraft(annotation) {
    if (isDefined(annotation.draftId)) {
      return this.task.drafts.find((possibleDraft) => possibleDraft.id === annotation.draftId);
    }
    return undefined;
  }
Finds the active draft for the given annotation.
@param {Object} annotation - The annotation object.
@returns {Object|undefined} The active draft or undefined if no draft is found.
@private