^^&&^^

Edit File: hidden-sidebar.php

<?php
/**
 * Title: Sidebar
 * Slug: twentytwentyfour/hidden-sidebar
 * Inserter: no
 */
?>

<div class="wp-block-group" style="padding-right:0;padding-left:0">
	
	<div class="wp-block-group" style="margin-top:0;margin-bottom:0">

<div class="wp-block-group">
			
			<h2 class="wp-block-heading" style="font-size:1.6rem"><?php esc_html_e( 'About the author', 'twentytwentyfour' ); ?></h2>

</div>
		
	</div>

<hr class="wp-block-separator has-text-color has-contrast-color has-alpha-channel-opacity has-contrast-background-color has-background is-style-wide"/>

<div class="wp-block-group">
		
		<h2 class="wp-block-heading" style="font-size:1.6rem"><?php esc_html_e( 'Popular Categories', 'twentytwentyfour' ); ?></h2>

</div>

<div class="wp-block-group">
		
		<div class="wp-block-group">
			
			<h2 class="wp-block-heading" style="font-size:1.6rem"><?php esc_html_e( 'Useful Links', 'twentytwentyfour' ); ?></h2>

<p class="has-small-font-size"><?php esc_html_e( 'Links I found useful and wanted to share.', 'twentytwentyfour' ); ?></p>
			
		</div>

</div>

<div class="wp-block-group">
		
		<h2 class="wp-block-heading" style="font-size:1.6rem"><?php esc_html_e( 'Search the website', 'twentytwentyfour' ); ?></h2>

</div>

<div style="height:var(--wp--preset--spacing--10)" aria-hidden="true" class="wp-block-spacer">
	</div>
	
</div>