static cleanup() {
    if (this.#pendingTextLayers.size > 0) {
      return;
    }
    this.#ascentCache.clear();

    for (const { canvas } of this.#canvasContexts.values()) {
      canvas.remove();
    }
    this.#canvasContexts.clear();
  }
Clean-up global textLayer data.
@returns {undefined}