Hi [USER=126614]@polarwoc[/USER]
The two functions to which you refer actually have a different action.
Clicking with Opt/Alt and the visibility eye icon hows that Layer by itself and if Opt/Alt click on eye icon is clicked again all the prior visible Layers are now again visible.
If one use the Opt/Alt on the Layer thumbnail, this zooms in to the Layer Edges for that one Layer. It does not turn off visibility of any of the other Layers. Note that the Layer edges are determined by the visible pixels (e.g. full transparency is not included in the Layer Edges. Under some circumstances it can seem that the other Layers are turned off though they are not. Example below:
This first image is 5 layers with numbers 0 to 4 in center and each corner all surrounded by transparency.
[ATTACH=full]137683[/ATTACH]
If I Alt/Opt Click on Layer 0 it zooms in to the zero (to its Layer Edges) yet all the other Layers are still visible just out of sight.
[ATTACH=full]137684[/ATTACH]
If I zoom out of this image you will see all of the Layers are visible (Note I turned the View > Show Extras> Layer Edges. The Layer Edges for Layer zero are shown and that was what was zoom in to.:
[ATTACH=full]137685[/ATTACH]
It appears that the other Layers are not visible yet that is not the case. You can do the same it Alt/Opt is done with any of the other Layers.
If a given Layer has not transparency, the Layer Edges are at the document boundaries and using the Alt/Opt on the Thumbnail only slightly enlarges so the Layer edges fill up the entire Workspace.
I am not sure if the other posts already covered this yet wanted to point out the misconception that when Alt/Opt click on thumbnail is only showing the one Layer when it is only zooming it the Layer Edges for that Layer. Just zoom back out and it will be clear.
Hope this helps
John Wheeler
