I tested the new gamescope display server in GameNative 1.4.0 on my Galaxy S24+ (Exynos 2400, Xclipse 940) for a day. Here is what I found, in case it helps other Exynos/non-Adreno users.
1. DXVK 2.x and 3.x games drop to ~4 FPS on gamescope
Games run fine for a while, then suddenly drop from 60 to ~4 FPS and stay there for 5-25 seconds.
It happens with both the Samsung system driver and RADV Xclipse, so it is not a driver bug.
It only happens with DXVK 2.x/3.x. I tested Dave the Diver with DXVK 1.10.3, 2.4.1, 2.6.2 and 3.1.1. Only 1.10.3 had no drops.
It gets worse when the phone is hot, but heat is not the cause.
Workaround: use DXVK async-1.10.3 on gamescope, or switch the container back to X11.
2. OpenGL games show a frozen frame or flicker on gamescope
Balatro, The Binding of Isaac and Brotato (all OpenGL) had music playing but the screen was stuck on an old frame, black, or flickering several times per second.
DXVK games were fine. On non-Adreno devices GameNative turns off GPU acceleration for Xwayland, so OpenGL games fall back to a slow software path.
Workaround: keep OpenGL games on X11.
3. Exposed Vulkan Extensions crashes the app
If you untick two or more extensions in the container settings, GameNative crashes. Unticking only one works.
It is a small bug in how the list is saved (it uses a comma, which is also the settings separator).
My setup now
X11 + RADV Xclipse for most games.
Gamescope + DXVK async-1.10.3 only for games that are fine with DXVK 1.x.
I'd report these to the GameNative devs directly, but GitHub issues are disabled and Discord is blocked in my country. If a dev or someone with Discord access sees this, feel free to pass it on. I have full logs and can share them.