improvised shelves

Hey! Your config entry looks correct. The most likely issue is permissions - you need to grant yourself the stacking permission for shelves. Based on your config shortname shelves_horizontal, run this command:

• oxide.grant group default objectstacks.shelves_horizontal.use
• (or for Carbon: c.grant group default objectstacks.shelves_horizontal.use)

The permission format is objectstacks.<shortname>.<tier>, and you also need to set up the tier with a max stack count in the permissions config. After that, look at a placed shelf and right-click with another shelf in your hand.