Scaffolding does not working properly at build height.

Steps:

1. Make a stack of scaffolding up to build height.
2. Extend the scaffolding to the side by clicking on the top of the stack.
3. Break the scaffolding directly next to the tower at the top.

The rest of the scaffolding that is not part of the tower stays even though it should break.  Also, the user is given a warning about build height even when the scaffolding is still placed to the side.