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I just started learning Blender and something happened. I have couple objects Cube, 2x Planes and Camera. But now all objects but Cube disappeared. If I choose them (in the right side panel), they have location, scale, dimension, but I can't see them. There is one thing I noticed. When I choose Cube (only visible object). In the properties panel is Item. But when I choose any other object the Item is not visible.
EDIT: thanks it was the / on numpad, just find out that regular / is not the same as numpad / And because my notebook does not have numeric keyboard I had to use Fn.