diff --git a/Assets/Scripts/Editor/ShipModPreview.cs b/Assets/Scripts/Editor/ShipModPreview.cs
index 090917d9e..64f9ea6b7 100644
--- a/Assets/Scripts/Editor/ShipModPreview.cs
+++ b/Assets/Scripts/Editor/ShipModPreview.cs
@@ -65,7 +65,8 @@ public static class ShipModPreview
                 ship.HullColliders[0].GetComponent<MeshCollider>() != null, "one hull collider with a MeshCollider");
         Require(Inside(ship.MapIcon) && Inside(ship.Shield) && Inside(ship.TractorBeam), "map icon, shield and tractor inside the ship");
         Require(ship.ThrusterHardpoints.Select(node => node.name).SequenceEqual(plan.Thrusters) &&
-                ship.ThrusterHardpoints.All(node => Inside(node) && Inside(node.Emitter) && node.Emitter.forceRenderingOff),
+                ship.ThrusterHardpoints.All(node => Inside(node) && Inside(node.Emitter) &&
+                    node.Emitter.sharedMaterials.All(material => material == ship.InvisibleMaterial)),
                 "thruster hardpoints with unrendered emitter meshes");
         Require(ship.RadiatorHardpoints.Select(node => node.name).SequenceEqual(plan.Radiators) &&
                 ship.RadiatorHardpoints.All(node => Inside(node) && Inside(node.Mesh)), "radiator hardpoints with meshes");
diff --git a/Assets/Scripts/Gameplay/ShipModShips.cs b/Assets/Scripts/Gameplay/ShipModShips.cs
index d60dc2a8c..354a1e4a6 100644
--- a/Assets/Scripts/Gameplay/ShipModShips.cs
+++ b/Assets/Scripts/Gameplay/ShipModShips.cs
@@ -123,9 +123,11 @@ public static class ShipModShips
         var thrusters = plan.Thrusters.Select(id =>
         {
             // The thruster's mesh is its exhaust's emission surface, never drawn (ruling thrusters-radiators-are-meshes).
+            // The invisible material is serialized, so it survives the prototype's clone, and EntityInstance keeps it as
+            // this renderer's visible material; forceRenderingOff would not survive Instantiate.
             var hardpoint = AddOrGet<ThrusterHardpoint>(Node(id).gameObject);
             hardpoint.Emitter = Renderer(id);
-            hardpoint.Emitter.forceRenderingOff = true;
+            hardpoint.Emitter.sharedMaterials = Enumerable.Repeat(template.Invisible, hardpoint.Emitter.sharedMaterials.Length).ToArray();
             return hardpoint;
         }).ToArray();
         var radiators = plan.Radiators.Select(id =>