How to show blank search on wordpress

By default, wordpress do not search for blank. It redirects to the home page for blank search. To prevent this we can use pre_get_posts hook. We can use pre_get_posts action to manipulate the query variables for specific pages. We can modify $wp_query object before any results are returned. In this example, we are using pre_get_posts before $wp_query returning false value. Use the following code on functions file inside your theme.

<?php // to avoid redirection from search result displaying in home page
function make_blank_search ($query){
global $wp_query;
if (isset($_GET['s']) && $_GET['s']==''){ //if search parameter is blank, do not return false
$wp_query->set('s',' ');
$wp_query->is_search=true;
}
return $query;
}
add_action('pre_get_posts','make_blank_search');
?>

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