The bug

In the Creative inventory, mangrove planks products such as the block itself, planks and fences come directly before the nether wood versions. However, stairs do not seem to follow this, instead being placed considerably after them.

How to reproduce

1. Open the Creative inventory to Building Blocks
2. Locate mangrove stairs
3. Locate the two nether wood stairs

Expected results

Mangrove stairs would come directly before crimson and warped stairs.

Actual results

They appear several lines later.