Tried looking. According to one of the users who posted it its by 0x00 whos the person who made floor 796. All things I can find relating to them are floor 796 related though and can’t find where this was originally posted
Heres floor 796 though if anyones interested https://floor796.com
For old reddit style theres mlmym which fills that niche better (e.g. for you that would be at https://old.lemmy.world)
Default UI is currently getting overhauled in a bunch of different ways. Lemmy-Leptos for Lemmy itself, and new UIs for Sublinks and Piefed as they get constructed