Error if post is too long

I’ve found an issue in your plugin. If any post is too big, the excerpt code is not working, making the content overflow the page. The only solution that works for me is to comment the code below in the functions.php file.

//if (empty($content_limit) && !empty($content_chars)) {
$slider_excerpt = substr($slider_content, 0, $content_chars);
//} else {
// $slider_excerpt =
smooth_slider_word_limiter($slider_content, $limit = $content_limit);
//}