wpseek.com
A WordPress-centric search engine for devs and theme authors

function dismissed_updates() {
	$dismissed = get_core_updates(
		array(
			'dismissed' => true,
			'available' => false,
		)
	);

	if ( $dismissed ) {
		$show_text = esc_js( __( 'Show hidden updates' ) );
		$hide_text = esc_js( __( 'Hide hidden updates' ) );
		?>
		<script type="text/javascript">
			jQuery( function( $ ) {
				$( '#show-dismissed' ).on( 'click', function() {
					var isExpanded = ( 'true' === $( this ).attr( 'aria-expanded' ) );

					if ( isExpanded ) {
						$( this ).text( '<?php echo $show_text; ?>' ).attr( 'aria-expanded', 'false' );
					} else {
						$( this ).text( '<?php echo $hide_text; ?>' ).attr( 'aria-expanded', 'true' );
					}

					$( '#dismissed-updates' ).toggle( 'fast' );
				});
			});
		</script>
		<?php
		echo '<p class="hide-if-no-js"><button type="button" class="button" id="show-dismissed" aria-expanded="false">' . __( 'Show hidden updates' ) . '</button></p>';
		echo '<ul id="dismissed-updates" class="core-updates dismissed">';
		foreach ( (array) $dismissed as $update ) {
			echo '<li>';
			list_core_update( $update );
			echo '</li>';
		}
		echo '</ul>';
	}
}