If specific hotbar used for scaffold becomes empty, and you have the SAME blocks in inventory, they will be moved onto your hotbar.

Thresold distance used to determine how far blocks can be placed. Range 0 - 0.5.
0 - means place block only if center of player lie above empty block. 0.5 - means place any blocks tangent to circle with radius 0.5 and centered with player center.

If there is no blocks to attach new block, module attempts to attach block to air blocks. May not work on your server.

Module places blocks "transparently", meaning it will not change selected slot on hotbar.