You’re welcome!
Since you first reported this issue, I’ve seen at least one other report of the exact same issue. Further investigation on my part has revealed that in both cases the “no sunlight on the avatar” issue has occurred on a Windows PC with an AMD CPU and GPU.
Since this appears to be a budding trend, I’ve flagged up the matter to a higher technical authority of the team and I’m waiting to see if we can get an official bug report. Thanks for your efforts in reporting this!