Thanks Elliot. I’ve been getting various answers on this across various forums, but nothing’s working unfortunately. Here are 2 things that I tried, per suggestions –
$args = array( 'post_type' => 'project', 'meta_query' => array('key' => 'homepage_slide', 'compare' => 'EXISTS'));
and
$args = array( 'post_type' => 'project', 'meta_query' => array('key' => 'homepage_slide', 'value' => 'true' , 'compare' => 'LIKE'));
It’s been awhile since I’ve been stumped by what started as a simple concept! I may not be thinking about this clearly…