It looks like it's the default dashboard setting. I think I tuned that off ages ago when it was first created.
I can see though, especially if you're newer to it and less comfortable with yaml due to all the UI improvements, that it's a bit of an imposition to figure out why it's happening and how to turn it off.
The fact that they keep adding stuff without making it easy to turn off is one of those little things that irk me about Home Assistant.