[Theme Horse Support Team]

Hi Cerstin,

If you will not set the featured image in the post then featured image section will be remove automatically.
If you want them and want to remove then just Go to Appearance -> Theme Options -> Design Options Tab -> Custom CSS paste the following CSS code and Click on save all changes button:

.blog .post-featured-image {
    display: none;
}

Could you also please help us rating this theme in WordPress Repository.
https://wordpress.org/support/view/theme-reviews/interface
We really appreciate your rating.

Thank you for using our theme!