Help with URL appearing on blog post that can't be deleted?

Hi all,

When I go to Edit mode a URL (that I've not added) is appearing at the bottom of the page. Does anyone know why it appears and how to delete?

https://www.parisarch.fr/news-entries/cantabria-study-trip-2023

On other parts of the site I've added a page header code injection for a filter, it looks like the blog post pages are picking the same code up as I get a message that the filter needs to be configured. When I asked the Squarespace customer service they said the URL is appearing because of this code, however, I've not added that code to these blog posts?

Please let me know if anyone has an idea why this is appearing. Thanks in advance!

#1. Which page do you see the url?

#2. You can use this code to Website > Website Tools > Custom CSS to hide Config button

/* Hide get config button */
.show-cf-get-filter-config-button .universal-filter-button {
    display: none !important;
    opacity: 0 !important;
}