BUG: Copying smart object with cmd+c unlinks it from the original

It depend on the version of Photoshop. What you wrote is somwhat like how CC 2018 and CC CC 2019 work on my machine  the other version of Photoshop I have installed do not work that way.  The other version of Photoshop I have installed are CS3, CS6 and CC 2014.   I have removed CC, CC 2015, CC 2015.5 and CC 2017 from my machine.  If a smart object layer is the current target and the is no Active Selection.  CMD+C  does not copy anything to the clipboard. The Clipboard remains empty or still has what was previously copied into the clipboard.

In CC 2018 and CC 2019 with not active selection  CMD+C followed by CMD+V works somewhat like menu Layer>Smart Objects>New Smart Object via Copy however. The Layers Associated  transform will not be copied correcty the object will be scaled correctly but the smart object layer content pisition will be centered over the center of the canvas. If the current target is a smart object layer. If the current target is a different type of layer a copy of the layer will be copied to the  clipboard and CMD+V will Paste in a new layer of the type  copied centered over the canvas.

In any case how it works in CC 2018 and CC 2019 is not correct. I woul agree with you the its a bug.

Yes but it just copies it in place, not in a new group or table

That dragging a Smart Object through the Pasteboard disrupts it’s file-reference does not seem unreasonable but neither does your expectation that it be maintained.

So I think you calling it a bug is justified, it’s just a bug that does not affect me as the copy-/pasting of Layers themselves has been introduced in Photoshop only fairly recently.

Maybe post the link so others may find your report and add their +1.

CMD+J created a new smart object layer that shares the originals smart object layers object. The Object is not changes at all if it was a object linked to a files its should still be a linked to that file.  You can move the new layer in the layer stack into to any layer group or create a new group with the layer in it.  I do not know what you mean by table.

CMD+A  Select all followed  by CMD+C Followed by a CMD+V Create a new raster layer not a smart object layer.

With the smart Object the active layer without a selection  CMD+C CMD+V should be the same as CMD+J New Smart Object layer the share the single object, However the shared part does not seem to be done correctly..

To create a new independent Smart object layer you   need to use menu Layer>Smart Objects>New Smart Object via copy.

When I edited the botton smart object shared object and made it red the smart object layer created with CMD+C CMD+V did not update.

So you are right the is a bug.