Could #1422 be related? CC: @youknowriad

@jasmussen I don't think so, this is a separate issue while searching uses the raw value of the post_content which includes the block comments and mess up with the results. wp:paragraph...

But this is not specific to Gutenberg, Gutenberg makes it more visible but this is a Core Bug that can be reproduced using shortcodes as well.

One new roadblock ?

Unfortunately, this is a known issue in WordPress core - in a vanilla WordPress install, if you search for "table", you'll get results including <table> tags. MySQL's string searching isn't capable of dealing with this kind of contextual parsing.

If you require 100% accurate search results, the best option is to use a dedicated search engine, like Elasticsearch. There are also Elasticsearch services available within the WordPress world, if setting up a dedicated search server is not an option.

Given Gutenberg blocks will add substantially more "hidden" strings, I wonder how much larger of a problem this will become. It'd be interesting to do some analysis comparing an English-language dictionary to partial string matches with Gutenberg blocks.

MySQL's string searching isn't capable of dealing with this kind of contextual parsing.

I found a way to do this, but I'm not sure if fiddling with posts_where would be okay for core or if this is plugin territory ...

<?php
/**
 * Plugin Name: Ignore block name in search
 * Description: Updated the native search to ignore block editor comments
 * Version: 1.0
 * Author: Torsten Landsiedel
 * License: GPL2
 */

/*
Based on "Search Ignore HTML Tags" by Pramod Sivadas
wordpress.org/plugins/wp-search-ignore-html-tags/
*/

/**
 * Modify search query to ignore the search term in HTML comments.
 *
 * @param string   $where The WHERE clause of the query.
 * @param WP_Query $query The WP_Query instance (passed by reference).
 *
 * @return string The modified WHERE clause.
 */
function tl_update_search_query( $where, $query ) {
	if ( ! is_search() || ! $query->is_main_query() ) {
		return $where;
	}

	global $wpdb;
	$search_query = get_search_query();
	$search_query = $wpdb->esc_like( $search_query );

	$where .= " AND {$wpdb->posts}.post_content NOT REGEXP '<!--.*$search_query.*-->' ";

	return $where;
}
add_filter( 'posts_where', 'tl_update_search_query', 10, 2 );

@pento Feedback if a trac ticket makes sense would be very much appreciated. Thanks in advance!

The code above is not working, but it seems there is a way for MariaDB 10.0.5+ and MySQL 8.0.4+, because then REGEXP_REPLACE was introduced. More details here: https://core.trac.wordpress.org/ticket/56294/