Light issue

Hello !
I noticed this problem, I don't found any previous issues about it, so here it is:
https://youtu.be/fAImXL54Juk
( I'm running last build, but I already got it on build #294 )

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Start by watching the linked YouTube video and reproducing the reported lighting problem on the latest build, comparing it with build #294. The issue does not name a source file, test, entry point, or expected behavior, so identify the affected subsystem and a clear reproduction before determining what done means.

Written by the indexing model from the issue text.