Since Prefabs are broken, you can make Selection sets instead.

Start by selecting all desired objects, then right click on it in the world, not the world outliner. From there, right click and select > Create New Selection Set.

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Give it an identifying name.

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Then you can click on any object from that selection, right click, and then choose Select Containing Set(s), and it will select the whole group.

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This is very handy for duplicating items that you might have created/mashed together to create something unique, and allows you to duplicate the entire set much faster than manually selecting each individual item.

You can add more objects to your selections set. I have this group of the table and objects on it. Right click on another table and select Manage selection sets.

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In the window choose your selection set and click on >> button to add the table to selected set.

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Now when I select containing set, the table selects as well.

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There are more options for selection sets in the context menu, you can try them yourself :)