Recently, I was doing my own business, when I discovered that GNOME Software shows no apps at all. However, I checked flatpak with flatpak remotes, and all the repos seem fine. I remember doing a reboot before it happened. I tried using rpm-ostree rollback, and, because I was using a Nvidia driver image courtesy of Universal Blue, I tried using the vanilla image. Nothing changed. I suspect it to be the cause of a broken config file somewhere…
Please tell me if you have any potential solutions 
EDIT: No installed apps are displayed either.