Quality problem: sort of pixelated-semi transparent-cube overlaying the scene

I’m started having light issues (everithing I tried to change they didn’t change) so I’ve decide to unistall completely unreal (even launcher and residual folder) from the pc and reinstall all from 0

Now lights work properly and the “cage” problem seems to have gone… I’m feeling confused! xD
@RynerAJ I didn’t tried completely: I tried with a complete white texture and the problem wasn’t gone