It’s extremely difficult to eliminate all the possibilities like in the original post.
For example, adding additional post type to a site would mean having additional problems in the future. Or returning posts that you don’t want from a post type you don’t really want for search results.
A better solution would be to make sure that you are currently querying a post type that can have ‘category’ as a term.
function alter_category_query($query) {
if(is_category() && empty($query->query_vars['suppress_filters'])
&& empty($query->query_vars['suppress_filters']) ||
$query->query_vars['suppress_filters'] == 'post') {
$query->set('post_type', array('course'));
return $query;
}
}
add_filter('pre_get_posts', 'alter_category_query');
The above will only make the change if you’re currently doing a query for posts and you won’t need to worry about future changes causing problems you’ll need to track down.
