How to store extra data in custom field except state?

public array $formCustomProperties = [];

public function setFormCustomProperties(array $properties): self
{
    $this->formCustomProperties = $properties;

    return $this;
}

->action(function (array $arguments, SpatieMediaLibraryFileUpload $component, $data): void {
    $formCustomProperties = $component->formCustomProperties;
    $formCustomProperties[$arguments['key']] = $data;
    $component->setFormCustomProperties($formCustomProperties);
})