Rings' rocks flickering & Saturn strange color on ultrawide screen

[Pitou]

Game Version​

2026.3.7.3848 and 2026.3.8.3883

Operating System​

Windows 11
NVidia RTX 5080
Reproduced with drivers 591.86, 595.79 and 595.97. (This is not driver related.)

What Happened​

I use 3 identical FullHD monitors merged as one ultrawide screen of 5760x1080. When flying in Saturn rings, rocks flicker when the camera is oriented in some directions. I can also see Saturn being white when it's near the edge of the screen.
2026.3.7.3848: It seems there is a 90° range where it flicker. When the camera is not oriented in this range (the other 270° of rotation), rocks are fine.
2026.3.8.3883: It seems to always flicker regardless of the view direction.

It doesn't reproduce when I use a single 1920x1080 monitor. Nor with a 120° FOV with 16:9 aspect ratio.

What Was Expected​

No graphical glitch on ultrawide monitor.

Reproduction Rate​

Always

Additional Info​

• Videos:
  2026.3.7.3848:
  
  
  2026.3.8.3883 (Saturn issue more visible):

Note: YouTube stretched (reduced) the video horizontally, thus the aspect ratio of the videos is wrong on YouTube.