For context, I made this bundle here, as you can see I 3D modelled it in a T position as it’s quite a bulky body and I wanted to get the arms right, otherwise the arms would clip into the body during the production process which would make weight painting, caging or touch-ups harder. When viewed on web it looks incorrect leading people to believe the arms would stay stuck like that in the T-pose position.
Web thumbnail example
However in-game the arms look as they should and follow the bones of the animations (idle, run, walk, etc) normally.
In-game example
Expected behavior
The thumbnail of avatar bundles should make sure that the thumbnail pose is exactly the same for every bundle. For example in-game any body you use, the bones of the body will snap to the animated idle or run animation regardless of size or position (for example, if you add my bundle in Studio it will appear in the position I modelled it in, if you use the bundle as a StarterCharacter and click play it will move normally).
My solution for the staff team would be to update the base pose for character bundle thumbnails to make sure that people who 3D model them in a T-pose don’t have this issue and the arms all stay at the sides as normal. A lot of us UGC creators make bodies this way as it is easier to model parts such as the hands rather than if they were in the A pose, and just rotating the arms won’t work 90% of the time. A lot of us would appreciate if this could be fixed 
I’ve provided the body file for staff to use if they wish to test a possible solution, thank you!
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