[] Groups do not properly duplicate

Some items are left out of groups when duplicating them.

Steps to Reproduce

  1. Place a canvas cube.
  2. Alt-drag it over 3 times
  3. Select all the cubes and try to duplicate them all with both copycat and alt-drag

What I expected to happen

Whole group to get copied

What happened

Just 3(?) duplicates are put into the copied groups, groups do not form on said copies.

Notes / Media