Microsoft Windows Stardust. It will replace Microsoft Windows Luna in its initial end of support.
Windows Stardust was first teased in a Microsoft forum. It included a Galaxy background and the Windows logo. This had many people guessing in what it could be, and a month later, it alongside its release date was officially announced through Microsoft's Twitter. Fans were desperate for details on this new version and what it could be.
At the End of Support of Windows Luna (01-01-2050), Microsoft announced that the date it will all end is the same as the release date for the new system, announced to be named Windows Nebula. This could mean only one thing: Windows Nebula will replace Windows Luna.
In a last minute pitch, Nebula was changed to Stardust.
The release date came and it was very well received, though not as well received as Luna.
It continued to be updated until 2063, where it reached its end of support.
Windows StardustAERO was planned to be the replacement for Stardust. But sadly, it was cancelled right when development was about to end in favor of Windows LunaFLORIS, which is basically Windows Luna fused with Windows Stardust, but MUCH better.
But alas, StardustAERO would not be fully canceled. It would follow suit a few years later.