Fix #3427

dist/preview release/babylon.max.js

@@ -11713,7 +11713,7 @@ var BABYLON;
                     }
                 }
             }
-            if (isTextureForRendering) {
+            if (isTextureForRendering && this._activeChannel > -1) {
                 texture._designatedSlot = this._activeChannel;
                 if (!isPartOfTextureArray) {
                     this._bindSamplerUniformToChannel(texture._initialSlot, this._activeChannel);

dist/preview release/customConfigurations/minimalGLTFViewer/babylon.max.js

@@ -11713,7 +11713,7 @@ var BABYLON;
                     }
                 }
             }
-            if (isTextureForRendering) {
+            if (isTextureForRendering && this._activeChannel > -1) {
                 texture._designatedSlot = this._activeChannel;
                 if (!isPartOfTextureArray) {
                     this._bindSamplerUniformToChannel(texture._initialSlot, this._activeChannel);

src/Engine/babylon.engine.ts

@@ -4635,7 +4635,7 @@
                 }
             }
 
-            if (isTextureForRendering) {
+            if (isTextureForRendering && this._activeChannel > -1) {
                 texture!._designatedSlot = this._activeChannel;
                 if (!isPartOfTextureArray) {
                     this._bindSamplerUniformToChannel(texture!._initialSlot, this._activeChannel);