SceneCapture2D appears to cause main viewport flicker in a static scene

Context: this report comes from a RenderFuzz-based UE 5.5 rendering anomaly study. I am posting the issue publicly so other Unreal Engine developers can check whether it is reproducible, already known, or has a practical workaround.

I have a UE 5.5 case where adding/enabling a SceneCapture2D seems to cause
visible flicker in the main viewport even though the camera and scene are
static.

Repro setup:

  1. UE 5.5 on Windows.
  2. Static test map.
  3. Observe the main viewport before SceneCapture2D is enabled.
  4. Enable SceneCapture2D and its render target.
  5. Compare adjacent frames in the main viewport.

Observed result:

The main view shows shading flicker after SceneCapture2D is active.

Expected result:

SceneCapture2D should not perturb the unrelated main viewport in a static
scene.

Evidence:

  • Attach evidence_sheets\06_创建SceneCapture2D导致闪烁.jpg.
  • Attach the minimal project showing SceneCapture2D toggled on/off.

Question:

Are there known cases where SceneCapture2D changes shared renderer state or
temporal history for the main view?

I also submitted this through the Unreal Engine Bug Submission Form and am using this thread to keep a public reproduction record.

Attachment note: I attempted to attach video_aligned.mp4 here, but this forum account is currently blocked by the forum’s new-user attachment restriction. The representative video was attached to the Unreal Engine Bug Submission Form submission and can be provided again when the forum allows attachments.