Wierd picture posted in website banner

When I created a blog post with some pictures, the first picture is displayed both in the blog content and in the banner section above the website main menu. How can I remove that?

ERPNext: v11.x.x-develop (d305a7a) (develop)

Frappe Framework: v11.x.x-develop (3bc8479) (develop)

Please add a screenshot.

Here you are. As you can see the picture in the blog is also posted in the banner. It happens both for standard and custom themes