Fixed double-counting of opacity when vertexColors are used

src/renderers/WebGLShaders.js

@@ -1207,7 +1207,7 @@ THREE.ShaderChunk = {
 
 		"#ifdef USE_COLOR",
 
-			"gl_FragColor = gl_FragColor * vec4( vColor, opacity );",
+			"gl_FragColor = gl_FragColor * vec4( vColor, 1.0 );",
 
 		"#endif"