[Feature]: Framed sliced stairs (center)

[ParasiticUniverse]

Describe the feature

The 2 new framed sliced stairs (slab and panel) could use a friend, where the center segment is the different one:

It could also have a vertical version.

[XFactHD]

This seems fairly niche to me, but I'll consider adding it in the future.

[stacode123]

This^