FR: Key of Cb?

[Watchful]

Well, this might seem petty, but I notice there's no scale/key for the key of Cb.

Yes, I know that's the key of B, but when working in Ab minor and dealing with transposing instruments, there are times when the key of Cb is a reality.

Oddly, there's a C# major, but that's not a conventional sheet-music-scoring key. But Cb, which appears more than a few times, is not represented. Can this be added?