Use the code below to customize the HTML displayed in a Dynamic List field.

add_filter('frm_show_it', 'custom_dynamic_list_display', 10, 3);
function custom_dynamic_list_display( $html, $value, $args ) {
if ( $args['field']->id == 30 ) { //change 30 to the id of the linked field ID
// Customize displayed value here
}
return $html;
}

Use the code below to show the full selected image in a Dynamic List field, instead of just the thumbnail.

add_filter( 'frm_show_it', 'custom_frm_show_it', 10, 3 );
function custom_frm_show_it( $html, $value, $args ) {
    if ( $args['field']->id == 30 ) { //change 30 to the id of the upload field in the other form
        $media_ids = explode( ', ', $args['value'] );
        $html = "<div class='frm_show_it'>";
        $new_value = '';
        foreach ( $media_ids as $media_id ) {
            $image = FrmProFieldsHelper::get_display_value( $media_id, $args['field'], array(
                'show_image' => true,
                'size' => 'full'
            ) );
            $new_value .= $image;
        }
        $html .= "<p>" . $new_value . "</p>";
        $html .= '</div>';
    }
    return $html;
}

If you are pulling data from a field with separate values, Dynamic List fields will show the saved value. If you would like to show the option label instead, use the code below. Just replace 485 with the ID of the field that your Dynamic List field is retrieving its value from.

add_filter('frm_show_it', 'dynamic_list_show_option_label', 10, 3);
function dynamic_list_show_option_label( $html, $value, $args ){
    if ( $args['field']->id == 485 && $args['field']->field_options['separate_value'] ) {
        foreach ( $args['field']->options as $option ) {
            if ( is_array( $option ) && isset( $option['value'] ) && $option['value'] == $value ) {
                $html = str_replace( $value, $option['label'], $html );
                break;
            }
        }
    }
    return $html;
}