wp_enqueue_classic_theme_styles() │ WP 6.1.0

Loads classic theme styles on classic themes in the frontend.

This is used for backwards compatibility for Button and File blocks specifically.

No Hooks.

Returns

null. Nothing (null).

Usage

wp_enqueue_classic_theme_styles();

Changelog

Since 6.1.0 Introduced.
Since 6.2.0 Added File block styles.
Since 6.8.0 Moved stylesheet registration outside of this function.

wp_enqueue_classic_theme_styles() code WP 6.9.1

wp-includes/script-loader.php 
function wp_enqueue_classic_theme_styles() {
	if ( ! wp_theme_has_theme_json() ) {
		wp_enqueue_style( 'classic-theme-styles' );
	}
}