WordPress at a glance
function is not described

WP_Theme::get_core_default_theme() public WP 4.4.0

Determines the latest WordPress default theme that is installed.

This hits the filesystem.

{} It's a method of the class: WP_Theme{}

No Hooks.

Return

WP_Theme/false. Object, or false if no theme is installed, which would be bad.

Usage

$result = WP_Theme::get_core_default_theme();

Changelog

Since 4.4.0 Introduced.

Code of WP_Theme::get_core_default_theme() WP 5.5.1

<?php
public static function get_core_default_theme() {
	foreach ( array_reverse( self::$default_themes ) as $slug => $name ) {
		$theme = wp_get_theme( $slug );
		if ( $theme->exists() ) {
			return $theme;
		}
	}
	return false;
}