In Magento you can have parameters at the end of your product image url. You can find this functionality here: '\Magento\Catalog\Model\View\Asset\Image::getUrlWithTransformationParameters'
In the Yireo_NextGenImages module we currently check for an image-extension ('.jpg', '.jpeg', '.png') at the end of the url. But having an image-extension not at the end of your url should also be valid in this case.
In Magento you can have parameters at the end of your product image url. You can find this functionality here: '\Magento\Catalog\Model\View\Asset\Image::getUrlWithTransformationParameters'
In the Yireo_NextGenImages module we currently check for an image-extension ('.jpg', '.jpeg', '.png') at the end of the url. But having an image-extension not at the end of your url should also be valid in this case.