Flickering rocks in background of hidden game (logo easter egg)

### Short summary

Background rocks flicker in the hidden easter egg game accessed via the app logo, after jumping up a few platforms.

### Affected version or release

v1.1.10

### Installation context

AppImage installation on Linux amd64, Wayland session. Visual glitch scoped to the hidden game screen only.

### What happened?

After clicking the app logo to open the hidden game, landing on the first platform, scrolling down so the prompt input is out of view, and jumping across a few platforms, the rocks in the background start flickering.

### Steps to reproduce

1. Open the app
2. Click the app logo to open the hidden game
3. Land on the first platform
4. Scroll down so the prompt input field is out of view
5. Jump across a few platforms to gain some height
6. Rocks appear in the background
7. The rocks start flickering

### Expected behavior

Background rocks should render normally and not flicker.

### Additional context

_No response_

Comienza en el punto de entrada app-logo del juego oculto y reproduce el parpadeo después de desplazar el prompt fuera de la vista y saltar entre plataformas. Sigue la ruta de renderizado de las rocas del fondo en Linux Wayland y verifica después que las rocas permanezcan estables en la misma secuencia y que el juego oculto siga renderizándose normalmente.

Escrito por el modelo de indexación a partir del texto del issue.