Today’s Question: I’ve noted since the last Photoshop update that layers that have a layer mask now appear with the layer mask icon rather than the black and white thumbnail reflecting the layer mask. Is there any way to change this?
Tim’s Quick Answer: Yes, you can enable the thumbnails for your layer masks in the Layers Panel Options dialog.
More Detail: You can choose the size for thumbnails on the Layers and Channels panels based on your preference, including a “None” option where image layers and layer masks will simply have an icon rather than a thumbnail that provides a preview of the layer or mask contents.
Start by clicking on the panel popup menu, which is an icon showing four horizontal lines found at the top-right corner of the Layers panel. Choose “Panel Options” from that popup menu, which will bring up the Layers Panel Options dialog.
In this case you’ll want to change the Thumbnail Size option from None to one of the thumbnail options. I personally prefer the largest thumbnail size, but you can try the different options to see what you prefer. Note that you do need to click the OK button in order for the Layers panel to update based on the setting you’ve chosen.
The same thumbnail options are available for the Channels panel as well, which you can access by choosing “Panel Options” from the panel popup menu for the Channels panel.