wp-includes/blocks/navigation.php:1198Sets fetchpriority="low" on all IMG tags within the navigation overlay.
$overlay_blocks_htmlstringstringfunction block_core_navigation_set_overlay_image_fetch_priority( string $overlay_blocks_html ): string { $tags = new WP_HTML_Tag_Processor( $overlay_blocks_html ); while ( $tags->next_tag( 'IMG' ) ) { $tags->set_attribute( 'fetchpriority', 'low' ); } return $tags->get_updated_html();}Introduced in 7.0.0. Unchanged from 7.0.4 through 7.1.0.
Signature, return type and hooks compared across 2 parsed releases.
src/wp-includes/blocks/navigation.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.