I think I accidentally deleted my response, so here it is again:
I would use jQuery for this and also add the tab to the field group beforehand. You’ll want to use the acf/input/admin_footer action.
It would look something like this:
add_action('acf/input/admin_footer', 'check_for_videos');
function check_for_videos(){
?>
<script>
var rowCount = jQuery('#acf-group_571814caa0f78 table tbody).find('tr');
if(rowCount ==0 ){
jQuery('tab field selector here').hide();
}
</script>
<?
}
It is sometimes difficult to nail down the exact name to use in the selector. For me it’s a trial and error thing.
