How to Fix a Blender Export Where Applied Modifiers Wipe Out Shape Keys

If a character loses its blendshapes whenever you tick Apply Modifiers on FBX export, the two features are fighting. Blender refuses to apply modifiers like Mirror or Subdivision onto a mesh that carries shape keys, so the export drops one or the other.

How to fix it

1. Turn off Apply Modifiers for morph meshes

In the FBX exporter, disable Apply Modifiers for meshes with shape keys. Bring the modifier result in another way rather than forcing the export to drop the morphs.

2. Apply modifiers non-destructively first

Use an add-on or the Apply Modifier with Shape Keys workflow to bake modifiers while preserving shape keys, then export with modifiers already baked.

3. Keep deform modifiers as runtime-only

Modifiers meant for in-engine behavior (like an Armature) should not be applied at all; let the engine drive deformation while shape keys export intact.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.