Sub-level desync produces "non-existent sub-level" warnings, then per-frame Aborting entity get for abnormally large AABB spam via ShoulderSurfing raytrace

[dizzyrune]

Description

Environment

• Minecraft 1.21.1, NeoForge 21.1.228
• Sable 1.2.2 (NeoForge)
• ShoulderSurfing 4.22.10
• Multiplayer, Prism Launcher
• Other relevant mods: Create, Distant Horizons, Sodium, Iris, Flywheel

What happens

After ~52 minutes of multiplayer play, the client logged:
[05:13:40] Received a sub-level movement packet for a non-existent sub-level
The bad state persisted silently for ~4 minutes. At 05:17:37, SubLevelInclusiveLevelEntityGetter.get began aborting with "abnormally large AABB" errors - one corner in normal world coordinates, the other in plot-grid coordinates (~10⁷ range), e.g.:
AABB[-1.94E7, 69.0, 1196.8] -> [572.2, 89944.5, 2.15E7]
The trigger is ShoulderSurfing's CrosshairRenderer.updateDynamicRaytrace → ProjectileUtil.getEntityHitResult → Level.getEntities, firing whenever the crosshair raytrace intersects an affected sub-level. Over the next ~2h 51min the error fired 51,301 times until I logged out - the client never recovered. Total log: 2,104,652 lines. Disabling ShoulderSurfing's dynamic crosshair stops the symptom.

Related issues

• Rapier3D internal error (island should be awake) #629 (open, unanswered): same mod combination (Sable + ShoulderSurfing), reporter suspected the same incompatibility. This report provides the diagnostic detail that one was missing, specifically the Received a sub-level movement packet for a non-existent sub-level warning preceding the AABB spam, and the call chain through CrosshairRenderer.updateDynamicRaytrace.

Game Log

https://mclo.gs/R2QBTyJ