It is my understanding the gltf/glb is now the recommended file format for saving and loading Three.js objects. However, there are problems with getting the colors to display properly. One proposed fix is to add the following instruction:
renderer.gammaFactor = 2.2;
I had been using a factor of 1. Changing it to 2.2 does appear to correct the color by making things brighter. (Although I had to change the color, roughness and reflectiveness of the model textures to make them look right again.)
One side effect is that is makes everything in the scene brighter, including the skybox textures.
Is there any way to avoid this side effect?
I am using Blender to create the gltf/glb file, so perhaps there is a box to check to eliminate the need for the gammaFactor adjustment?.