wp_add_editor_classic_theme_styles()

wp_add_editor_classic_theme_styles( array $editor_settings ): array

function wp_add_editor_classic_theme_styles( $editor_settings ) {
	_deprecated_function( __FUNCTION__, '6.8.0', 'wp_enqueue_classic_theme_styles' );

	if ( wp_theme_has_theme_json() ) {
		return $editor_settings;
	}

	$suffix               = wp_scripts_get_suffix();
	$classic_theme_styles = ABSPATH . WPINC . "/css/classic-themes$suffix.css";

	/*
	 * This follows the pattern of get_block_editor_theme_styles,
	 * but we can't use get_block_editor_theme_styles directly as it
	 * only handles external files or theme files.
	 */
	$classic_theme_styles_settings = array(
		'css'            => file_get_contents( $classic_theme_styles ),
		'__unstableType' => 'core',
		'isGlobalStyles' => false,
	);

	// Add these settings to the start of the array so that themes can override them.
	array_unshift( $editor_settings['styles'], $classic_theme_styles_settings );

	return $editor_settings;
}