我也在试着这么做

<?php

class My_Dropdown_Category_Control extends WP_Customize_Control {

    public $type = \'dropdown-category\';

    protected $dropdown_args = false;

    protected function render_content() {
        ?><label><?php

        if ( ! empty( $this->label ) ) :
            ?><span class="customize-control-title"><?php echo esc_html( $this->label ); ?></span><?php
        endif;

        if ( ! empty( $this->description ) ) :
            ?><span class="description customize-control-description"><?php echo $this->description; ?></span><?php
        endif;

        $dropdown_args = wp_parse_args( $this->dropdown_args, array(
            \'taxonomy\'          => \'product_cat\',
            \'show_option_none\'  => \' \',
            \'selected\'          => $this->value(),
            \'show_option_all\'   => \'\',
            \'orderby\'           => \'name\',
            \'order\'             => \'ASC\',
            \'show_count\'        => 1,
            \'hide_empty\'        => 1,
            \'child_of\'          => 0,
            \'exclude\'           => \'\',
            \'hierarchical\'      => 1,
            \'depth\'             => 0,
            \'tab_index\'         => 0,
            \'hide_if_empty\'     => false,
            \'option_none_value\' => 0,
            \'value_field\'       => \'term_id\',
        ) );

        $dropdown_args[\'echo\'] = false;

        $dropdown = wp_dropdown_categories( $dropdown_args );
        $dropdown = str_replace( \'<select\', \'<select \' . $this->get_link(), $dropdown );
        echo $dropdown;

        ?></label><?php

    }
}


function olsen_light_child_customize_register( WP_Customize_Manager $wp_customize ) {
    require_once get_stylesheet_directory() . \'/inc/dropdown-category.php\';

    $wp_customize->add_section( \'homepage\', array(
        \'title\' => esc_html_x( \'Test-Link\', \'customizer section title\', \'olsen-light-child\' ),
    ) );

    $wp_customize->add_setting( \'home_slider_category\', array(
        \'default\'           => 0,
        \'sanitize_callback\' => \'absint\',
    ) );

    $wp_customize->add_control( new My_Dropdown_Category_Control( $wp_customize, \'home_slider_category\', array(
        \'section\'       => \'homepage\',
        \'label\'         => esc_html__( \'Slider posts category\', \'olsen-light-child\' ),
        \'description\'   => esc_html__( \'Select the category that the slider will show posts from. If no category is selected, the slider will be disabled.\', \'olsen-light-child\' ),
    ) ) );
}

add_action( \'customize_register\', \'olsen_light_child_customize_register\' );

<a href="<?php echo get_term_link(get_theme_mod(‘home_slider_category’))?>"><span><?php echo get_theme_mod(\'gs_slider_one_txt\')?></span></a>