substr encoding problems

First of all: Thanks for this great and easy to use plugin!
But I had some issues with unicode characters in the portfolio content. I resolved it by changing line 28 in shortcode-data.php to
$newString = mb_substr($string, 0, 50, mb_detect_encoding($string));
I just wanted to let you know, maybe others have the same problem ??

https://www.ads-software.com/plugins/full-width-responsive-portfolio/