Why is it dark mode when I use light mode?

[RixInGithub]

Lighthouse, when I make my site perfectly, it turns to dark mode even though I use light mode. What is wrong? Is it meant to be an easter egg? Here's the screenshot ( 0% inspect ) :

[adamraine]

Lighthouse is supposed to do a fireworks animation if you reach all 100s. Part of that animation is forcing the report into dark mode. Unfortunately, fireworks are currently borked #12563 so all you get is the dark mode switch. I think this confusion might give us a reason to address that P3 bug.