Updated builds.

build/three.js

@@ -14645,6 +14645,17 @@
 
 					};
 
+					// enable code injection for non-built-in material
+					Object.defineProperty( boxMesh.material, 'envMap', {
+
+						get: function () {
+
+							return this.uniforms.tCube.value;
+
+						}
+
+					} );
+
 					objects.update( boxMesh );
 
 				}
@@ -14675,6 +14686,17 @@
 
 					planeMesh.geometry.removeAttribute( 'normal' );
 
+					// enable code injection for non-built-in material
+					Object.defineProperty( planeMesh.material, 'map', {
+
+						get: function () {
+
+							return this.uniforms.t2D.value;
+
+						}
+
+					} );
+
 					objects.update( planeMesh );
 
 				}

build/three.module.js

@@ -14639,6 +14639,17 @@ function WebGLBackground( renderer, state, objects, premultipliedAlpha ) {
 
 				};
 
+				// enable code injection for non-built-in material
+				Object.defineProperty( boxMesh.material, 'envMap', {
+
+					get: function () {
+
+						return this.uniforms.tCube.value;
+
+					}
+
+				} );
+
 				objects.update( boxMesh );
 
 			}
@@ -14669,6 +14680,17 @@ function WebGLBackground( renderer, state, objects, premultipliedAlpha ) {
 
 				planeMesh.geometry.removeAttribute( 'normal' );
 
+				// enable code injection for non-built-in material
+				Object.defineProperty( planeMesh.material, 'map', {
+
+					get: function () {
+
+						return this.uniforms.t2D.value;
+
+					}
+
+				} );
+
 				objects.update( planeMesh );
 
 			}