wp_auth_check_html() WordPress Function

function wp_auth_check_html() {
	$login_url      = wp_login_url();
	$current_domain = ( is_ssl() ? 'https://' : 'http://' ) . $_SERVER['HTTP_HOST'];
	$same_domain    = ( strpos( $login_url, $current_domain ) === 0 );

	/**
	 * Filters whether the authentication check originated at the same domain.
	 *
	 * @since 3.6.0
	 *
	 * @param bool $same_domain Whether the authentication check originated at the same domain.
	 */
	$same_domain = apply_filters( 'wp_auth_check_same_domain', $same_domain );
	$wrap_class  = $same_domain ? 'hidden' : 'hidden fallback';

	?>
	<div id="wp-auth-check-wrap" class="<?php echo $wrap_class; ?>">
	<div id="wp-auth-check-bg"></div>
	<div id="wp-auth-check">
	<button type="button" class="wp-auth-check-close button-link"><span class="screen-reader-text"><?php _e( 'Close dialog' ); ?></span></button>
	<?php

	if ( $same_domain ) {
		$login_src = add_query_arg(
			array(
				'interim-login' => '1',
				'wp_lang'       => get_user_locale(),
			),
			$login_url
		);
		?>
		<div id="wp-auth-check-form" class="loading" data-src="<?php echo esc_url( $login_src ); ?>"></div>
		<?php
	}

	?>
	<div class="wp-auth-fallback">
		<p><b class="wp-auth-fallback-expired" tabindex="0"><?php _e( 'Session expired' ); ?></b></p>
		<p><a href="<?php echo esc_url( $login_url ); ?>" target="_blank"><?php _e( 'Please log in again.' ); ?></a>
		<?php _e( 'The login page will open in a new tab. After logging in you can close it and return to this page.' ); ?></p>
	</div>
	</div>
	</div>
	<?php
}