Quick answer: Unity VFX Graph reverting to default behavior after switching build target? Per-platform compiled shaders dropped - re-import VFX assets after target switch.
Switched from PC to Android target. VFX previewed correctly on PC; Android run shows default cube particles.
Reimport VFX Graphs
Select all .vfx assets; right-click > Reimport. Per-platform shader compile triggers.
Or use Build Profiles
Build Profiles in 2023.3+ track asset state per target. Switching profile triggers required reimports.
Verify in build log
Build output includes VFX compile info. Empty = the reimport didn't happen.
“VFX Graph compiles per-platform. Target switches require recompile.”
Add 'reimport VFX' to your build-target switching checklist. The bug is silent in dev; visible in build.