If you organized layers in folders, you can use layer Paste Options to duplicate a layer folder structure or just selected layers contained in a folder. By default, the duplicates of folders, layers, and objects use the source's name along with an appended number. For example, if the source layer name is curves, the duplicated layer is namedcurves#2.
, and then turn on Always Ask.The duplicate layer folders now appear at the bottom of the object list.
You can choose to paste a copied layer inside or outside the layer folder.
, and then turn on Always Ask.Duplicate Layers (Outside) to paste objects into copies of the layer outside its source folder.
The duplicate layers now appear at the bottom of the object list.
Duplicate Layers (Inside) to paste objects into copies of the layer inside its source folder.
To merge the contents of all duplicate layers into the original (and delete the duplicate layers) use Layers > Delete > Merge Duplicate Layers
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