Styles not displayed in Editor

Hi,

i use this code to display my CSS-codes in the editor:

<?php
// Load CSS Variables in Editor
add_filter('block_editor_settings_all', function($editor_settings) {
    $style_path = get_stylesheet_directory() . '/style.css';
    if (file_exists($style_path)) {
        $css_style = file_get_contents($style_path);
        $editor_settings['styles'][] = ['css' => $css_style];
    }

    $customizer_css = wp_get_custom_css_post();
    if (isset($customizer_css->post_content)) {
        $css_customizer = $customizer_css->post_content;
        $editor_settings['styles'][] = ['css' => $css_customizer];
    }

    return $editor_settings;
});

But all my buttons that I have loaded from a staging environment via the WordPress importer are displayed in the frontend, but not in the WP editor.