Accessing data in active effects via @ symbol

getRollData() {
    // Starts off by populating the roll data with a shallow copy of `this.system`
    const data = { ...this.system }

    // Copy the ability scores to the top level, so that rolls can use
    // formulas like `@str.mod + 4`.
    if (data.abilities) {
      for (let [k, v] of Object.entries(data.abilities)) {
        data[k] = foundry.utils.deepClone(v)
      }
    }

    return data
  }

getRollData() {
    // Starts off by populating the roll data with a shallow copy of `this.system`
    const data = { ...this.system }

    // Copy the ability scores to the top level, so that rolls can use
    // formulas like `@str.mod + 4`.
    if (data.abilities) {
      for (let [k, v] of Object.entries(data.abilities)) {
        data[k] = foundry.utils.deepClone(v)
      }
    }

    return data
  }