App already running!

I have a weird issue. Everytime I am loading my page (see the picture), I am getting a popup with “App already running!” even on my live version, hosted on digital ocean. Does someone know what the problem is and how to remove it?

Can you check your page includes, how many times is the appconnect js included?

Okay I checked everything and It seemed like I used an empty layout page, after deleting it the error disappeared. Thanks!