Ok, it has something to do with CSS. I removed this from additional CSS. I forgot about that as I’m using a theme from the site library. But, now instead of a block that is grey with the text “related posts” I just have the text without the grey block.
/* WPSP related Posts */
.wpsp-related-posts {
background-color: rgba(0,0,0,.03);
padding: 64px;
-webkit-box-sizing: border-box;
box-sizing: border-box;
}
.wpsp-related-posts h2 {
text-align: center;
margin-bottom: 1em;
}