Dynamic Custom Header Replacement

DUK

Installation Instructions

1. Upload the plugin files to the /wp-content/plugins/plugin-name directory, or install the plugin through the WordPress plugins screen directly.
2. Activate the plugin through the ‘Plugins’ screen in WordPress

How can I disable the regular featured image from displaying on a single post or page?

For the Twenty Seventeen theme you can change the header.php file to disable the regular featured image.
For example:
(lines 44 – 49)

    // If a regular post or page, and not the front page, show the featured image.
    //  if ( has_post_thumbnail() && ( is_single() || ( is_page() && ! twentyseventeen_is_frontpage() ) ) ) :
    //    echo '<div class="single-featured-image-header">';
    //    the_post_thumbnail( 'twentyseventeen-featured-image' );
    //    echo '</div><!-- .single-featured-image-header -->';
    //  endif;

What about foo bar?

N/A