<?php 
if( class_exists( 'WP_Customize_control' ) ){

    class Walker_Core_Custom_Text extends WP_Customize_Control{
        public $type = 'walker-core-custom-text';
        /**
        * Render the content on the theme customizer page
        */
        public function render_content()
        {
            ?>
            <label>
                <strong class="customize-text_editor"><?php echo wp_kses_post( $this->label ); ?></strong>
                <br />
                <span class="customize-text_editor_desc">
                    <?php echo wp_kses_post( $this->description ); ?>
                </span>
            </label>
            <?php
        }
    }
    
}
add_action( 'customize_register', 'Walker_Core_Custom_Text' );