We have renamed Post Grid plugin to Post Grid Combohttps://pickplugins.com/rebranding-of-our-post-grid-plugin/

accordions_main_no_content

add_action('accordions_main_no_content', 'accordions_main_no_content_18032020', 10);

function accordions_main_no_content_18032020(){

    ?>
    <p>Custom content here </p>
    <?php
}

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