Sunshine stream of Gaming Mode to Moonlight Client results in distorted streamed image. Works fine in Desktop mode.

[ZainAjam]

Describe the bug

When I start a Moonlight connection to my Minisforum Hx99g device running in Gaming Mode with Sunshine installed, I get a weird distorted image streamed. It looks like this on my Moonlight device. This is only a problem in Gaming Mode. Works fine in Desktop mode.

What did you expect to happen?

Instead of the stream being in the top left quadrant of the screen, I expect it to fill the screen, and without all the other distorted quadrants of colours around it.

Output of rpm-ostree status

No response

Hardware

HTPC image of Bazzite v3.0.1
Minisforum HX99G
2 x 16gb DDR5 4800mhz ram
1 x 500gb NVME storage drive (Bazzite installed on)
1 x 1000gb NVME storage drive (formatted as ext4 and set for mounting with KDE partition manager)
Xbox Series S controller with Xbox Wireless Dongle receiver
Pepper jobs remote control with usb receiver

Extra information or context

No response

[Zaunei]

I could also observe a very similar behavior as soon as I change the resolution in the game. Everything looks fine on the real monitor.

What else I could observe: As soon as the Steam overlay is visible, the Moonlight client fills the entire screen again.

My setup is a thin client with AMD 2400GE running Bazzite and various Moonlight clients (Mac, Apple TV). I don't have this problem with Steam Link.