This is a paid asset, but now you can download Grouping Tool for FREE, Please keep in mind this package is provided only for learning purposes or to be able to test before buying the product, NOT FOR COMMERCIAL PURPOSES.
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Grouping Tool v1.0.0 (Latest version)
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Easily group GameObjects together right in the Unity Hierarchy Panel from the context menu or with a keyboard shortcut (Cmd+G on Mac or Ctrl+G on Windows).
By default objects are grouped into an empty GameObject.
You can use your own Prefab template for grouping objects. Set the object template in “Window > Grouping Tool > Group Template” . Use context menu or keyboard shortcut to group objects with your custom Prefab Parent template (Cmd+Shift+G on Mac or Ctrl+Shift+G on Windows).