release() {
    if (this.canvas_ && this.canvas_.parentNode) {
      this.canvas_.parentNode.removeChild(this.canvas_);
    }

    // Clean up resize observer if it exists
    if (this.resizeObserver_) {
      this.resizeObserver_.disconnect();
      this.resizeObserver_ = null;
    } else {
      // Remove window resize listener if we were using that
      window.removeEventListener('resize', () => this.resizeCanvas_());
    }

    super.release();
  }
Releases the watermark instance and cleans up the canvas element.
@override