PHP Code snippet execution error

Hi
I am not sure if the issue is directly related to GP or not and whether I should be putting up this query in this forum. I have recently installed WPFORO forum plugin and everything works fine with GP theme. However, I am facing issues in executing a particular PHP code snippet. I am using Code Snippets and GP Child Theme

add_filter('wpforo_content_after', 'wpforo_default_attachment_image_embed', 11);
function wpforo_default_attachment_image_embed( $content ){
    if( preg_match_all('|<a class=\"wpforo\-default\-attachment\" href\=\"([^\"\']+)\"[^><]*>.+?<\/a>|is', $content, $data, PREG_SET_ORDER) ){
        foreach($data as $array){
            if(isset($array[1])){
                $file = $array[1];
                $e = strtolower(substr(strrchr($file, '.'), 1));
                if( $e == 'jpg' || $e == 'jpeg' || $e == 'png' || $e == 'gif' ){
                    $filename = explode('/', $file); $filename = end($filename);
                    $html = '<a href="' . esc_url($file) . '" target="_blank"><img class="wpforo-default-image-attachment" src="' . esc_url($file) . '" alt="' . esc_attr($filename) . '" title="' . esc_attr($filename) . '" /></a>';
                    $content = str_replace($array[0], $html, $content);
                }
            }
        }
    }
    return $content;
}

Link: https://wpforo.com/community/how-to-and-troubleshooting-2/uploading-and-embedding-images/

I got in touch with WPForo Support and they have replied that the code works fine at their end.

Screenshots:
https://prnt.sc/nz4ezp
https://prnt.sc/nz4f4a

Warmest Regards
BM

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