Gutenberg Full Site Editing

There’s a compatibility issue between Relevanssi and Gutenberg Full Site Editing. No results are found when you create a Query Loop to display the search results with Relevanssi enabled. The blank results happen because the post template block doesn’t use the Relevanssi results but instead uses a new WP_Query. Since Relevanssi still blocks the default search, this comes up empty.

For a straightforward solution, add this to your site:

add_filter( 'relevanssi_search_ok', function( $ok, $query ) {
  if ( ! empty( $query->query_vars['s'] ) ) {
    $ok = true;
  }
  return $ok;
}, 10, 2 );

This function hooks to the relevanssi_search_ok filter hook. This hook fires because Relevanssi looks at the newly-created WP_Query, but since it’s not the main query for the template, Relevanssi doesn’t take over. This function instructs Relevanssi to take over as long as there’s a s parameter in the query, and a search term exists.

Excerpts

The core WP excerpt block does not allow Relevanssi highlights in excerpts. It will display Relevanssi excerpts (restricted to the excerpt length in the block settings – make sure the setting in the block is higher than the Relevanssi excerpt length setting), but no highlights will be visible because all the excerpts are passed through wp_trim_words() which removes HTML tags.

This function can be used to overcome this limitation:

add_filter( 'wp_trim_words', function( $text, $num_words, $more, $original_text ) {
	global $post;
	if ( isset( $post->relevance_score ) ) {
		return $post->post_excerpt;
	}
	return $text;
}, 10, 4 );

If the post has the relevance_score attribute set – which should only happen within a search context – this function will cause the wp_trim_words() to return the original post excerpt.

With Max Mega Menu, the function above will add the excerpts to the menu items. You can avoid that:

add_filter( 'wp_trim_words', function( $text, $num_words, $more, $original_text ) {
	global $post;
	if ( ! empty( $text ) && isset( $post->relevance_score ) ) {
		return $post->post_excerpt;
	}
	return $text;
}, 10, 4 );

Restrictions

Relevanssi cannot add the highlight parameter to the permalinks in FSE themes. This means you cannot use the “Highlight in documents” feature.