Flatpak apps not rendering properly

I’ve got a couple of Flatpak apps (Kobo Deluxe and Uplink) that aren’t rendering properly. They appear in an unmovable display in the upper-left corner and are scaled up to fill the screen - which means, if they’re supposed to appear in a 640x480 window (for instance), you only see a small chunk of the screen. I’ve looked all over the web, but nothing I’ve tried has had any effect. Any ideas on how to get these apps to render in a proper, movable window at 1:1 scale?

Have you confirmed that this is a Flatpak-specific issue?

Because this could be an issue with your window manager as well.

To this regard, it would help to know what you are using as distribution, desktop and protocol (X11 or Wayland).

I’m using Bazzite with the KDE desktop. How do I check what protocol I’m using?

You should be able to check the protocol on the about page of the system settings.

For now, I would say the KDE folks probably know better where the issue might lie. So you might want to ask there as well:

Looks like it’s Wayland, then. I’m going to try using Distrobox to compile it and see if it behaves differently than the Flatpak version.