I’ve been having a little play, and it can be hidden with a bit of CSS for a short term fix:
.composer-popup.custom-body {
display: none;
}
I checked it against the ‘Your Topic is Similar to’ pop-up, and that one still appears as it has its own class, but I don’t know how many pop-ups are included in custom-body? I mainly use my mobile, so I don’t see these very often. 