I remember having an issue with this, it's some random option in the background settings, I haven't launched this in years but I think it's Depth or Distant effect or something

Turns out the steps are:
> Advanced UI at the top-right (this should always be enabled, its stupid we have to click it every time the software is launched)
> Environment on the right
> Customization > Post Processing > Depth of Field
Then toggle the slider (yes its a slider but the options are either on/off) whichever way

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