If you see the following error on your homepage hero section:
Warning : array_merge (): Argument # 1 is not an array in /www/htdocs/server/site/wp-content/themes/opSmartTheme/template-parts/homepage/homepage-hero-featured-post.php on line 122
This issue is most likely caused by you having your Blog > Homepage Hero > Hero Layout set to “Featured Post” but you have no posts created on your WordPress site
How to fix
Option 1: Create at least one post on your blog and ensure it is published. You can do this by going to Posts > Add New, and then create a post there.
Option 2: Change the homepage hero Layout option to one of the other options which do not use blog posts.