Helpful Hitboxes (Forge)

You can find the Fabric version here!

In vanilla, scaffolding changes its hitbox to a full cube when you're looking at it with another scaffolding block:

This makes it much easier to place! Helpful Hitboxes gives this behavior to fence, pane and chain blocks as well, eliminating the painful mouse positioning you had to do to place them on top of each other.

The new behavior:

This mod seems to work if you only have it on the client, meaning you can use it on vanilla servers. The fact that this is possible is strange, because it actually increases the area where you mouse can click to place a block. Due to this, some servers might consider its use cheating, so you should always ask permission first before using Helpful Hitboxes on a server. It's also entirely possible that a more advanced anticheat will break the mod, so there are no guarantees about it working client-only in every situation. Installing it on the server without players having Helpful Hitboxes locally is possible, but it will probably look buggy for them as the hitbox they can see won't have changed.