**Blender Version**
3.3.0-alpha+master.6ad9d8e2247d-windows.amd64-release
**Short description of error**
**Exact steps for others to reproduce the error**
1. Create an object
2. Add color attribute layer, optionally paint something on it with Vertex Paint
3. Export as glft/glb
4. Make sure the Vertex Color export option is enabled in Geometry tab
5. gltf doesn't have vertex color
Opening the gltf you can see that the attributes are:
```
"attributes" : {
"POSITION" : 0,
"NORMAL" : 1,
"TEXCOORD_0" : 2
},
```
COLOR_0 is missing
{F13264690}
{F13264687}