AFAIK objects such as sounds and decals used to be parented to the selected object when inserted.
This workflow was great if you for example wanted to copy a decal ID, because you knew exactly where it was inserted.
After the change, you now have to click a decal in the toolbox, then click on a part in the viewport, find the selected part in the explorer and then copy the decal ID. This gets pretty annoying after a while.