I've been working on a file. I have suddenly lost the ability to select individual layers in that file; i.e., selecting a layer does not highlight the layer. I can toggle the visibility of the layer; however, alt+click will not hide all other layers. I can not activate a mask on a layer. Strangely, I can click on a layer, then shift+click on some other layer in the stack to select (and highlight) a group of layers. If I duplicate that group into a new document, all operations are normal (highlight a single layer, move from image to mask, alt+click, etc.). So, it's something to do with that particular file. No layers are locked. No auto select.
I can easily work around by just duplicating all layers into a new document. Then, everything is back to normal. But I would like to know what might be causing the problem just to further my understanding. Any insight would be greatly appreciated.
Could you please post a screenshot taken at View > 100% and with the pertinent Panels (Layers, Channels, Options Bar, …) visible?
You seem to have activated Quick Mask Mode (Q).
Thanks very much.