Redux Framework slides field – wp_editor instead of textfield

I’m trying to customize slides default field (slides field – Redux framework) in order to include wp editor instead of textarea (description area)

original file is here : https://raw.githubusercontent.com/ReduxFramework/redux-framework/master/ReduxCore/inc/fields/slides/field_slides.php

So far I have changed this part of the code

if ( $this->field[ 'show' ][ 'description' ] ) {
$placeholder = ( isset ( $this->field[ 'placeholder' ][ 'description' ] ) ) ? esc_attr ($this->field[ 'placeholder' ][ 'description' ] ) : __ ( 'Description', 'redux-framework' );
echo '<li><textarea name="' . $this->field[ 'name' ] . '[' . $x . '][description]' .   $this->field['name_suffix'] . '" id="' . $this->field[ 'id' ] . '-description_' . $x . '" placeholder="' . $placeholder . '" class="large-text" rows="6">' . esc_attr ( $slide[ 'description' ] ) . '</textarea></li>';
}

to this:

if ( $this->field[ 'show' ][ 'description' ] ) {
$placeholder = ( isset ( $this->field[ 'placeholder' ][ 'description' ] ) ) ? esc_attr ( $this->field[ 'placeholder' ][ 'description' ] ) : __ ( 'Description', 'redux-framework' );
$editor_id =  $this->field[ 'id' ] . '-description_' . $x;

echo '<li> '.wp_editor( $content, $editor_id ,array("textarea_name" => ''.$this->field[ 'name' ] . '[' . $x . '][description]' . $this->field['name_suffix'].'' ));'</li>';
}

so, I’m getting wp_editors inside slides, but the problem is, I can not save any content,
BTW each dynamically generated editor text field has unique name and id, like in the original code.

UPDATE

just notice that editor doesn’t keep the content after page refresh, but stores the data on the first submit.