How to create blur layer?

Question

Adobe Photoshop

Please tell me how to create a translucent layer that will blur what is under it. Attachment example.

Answer 1

There is such a way: select all the layers that need to be blurred, transfer them to a smart object, and already apply a blur filter to this smart object. In this case, if you double-click on the layer thumbnail of the created smart object, a new document will open with the original layers that can be edited. If this document is saved, then the changes will be made to the editable smart object.

Answer 2

And yet, for sites, this is done using CSS:

.class {
  filter: blur(20px);
}

But that's another story)

Answer 3

No way. The blur must be applied directly to the original layer.