Weird behaviour when baking geometries with group

Hello there,

I encountered a very weird behaviour when baking geometries with group component. This has never happened to me or on other stuffs I did in the past.

Basically what happened is, when I bake geometries without group component, everything is okay and file is extremely light. However, when I tried to group my objects together and then bake the same objects, somehow, the file size increased dramatically and geometries are automatically assigned red colours (which I didnt assign any properties,colour, materials to my object). Please see the attached images.

I thought it’s just display thing in the beginning. However, when I started exporting the files, somehow the size of the files baked from the group component increased from about 1.5 MB to almost 2GB. This becomes an issue as the overall file goes up to almost 120 GB.

I double checked if there is a duplicated object, but no. Same number of objects for both files. See the image below.I tired to simplify the file for demonstration.

Can anyone explain to me why this happened? Is it a bug or some sort?

It’s very weird that geometries are automatically assigned colour properties.

Thank you.