It's a fake OS that (i think so) Verbose the Talking Cat made it (his video: When A Gamer Installs Windows 99), it is an hidden (fake) OS that looks so new, yet it is made from combining 2 old windows versions (Windows 98 and Windows 1.00), It has many bugs and glitches, but also, LORE, and any time you try upgrading or downgrading to something else, it blocks you from doing so, outages cant turn off the computer Windows 99 is in, so basically, Windows 99 is an secret (fake) OS hidden by Microsoft, and it has LORE.
1: Have you seen Windows 99, the Secret hidden OS?
2: I think so, the computer in my basement has it installed after i switched from Windows 1.00 to Windows 98