Yes using a wacom tablet. I exclusively work with a pen and tablet, and don't have a mouse I can test with (at least not a non-wacom mouse).
However, some other folks on the adobe community page alerted me that this was a bug, so I assume it does the same with a mouse.
I am using an iMac and a mouse and can confirm that it is as Lisa describes. Make a selection, then Cmd+Opt+Click a layer thumbnail and PS subtracts from the selection as it should, but also zooms which it shouldn't. This new annoying behavior was introduced with PS 2020.
I am on High Sierra with 21.0.1
This help file says what PS should do with Cmd+Opt+Click:
Jane - Thank you for confirming that it does the same thing with a mouse! I guess it's not my tablet..Certainly hope this is fixed soon.
I forgot to include my OS - I am on Mac Catalina 10.15.1, and have the latest photoshop CC 2020 update installed.
I'm sorry! I sit corrected. Yeah, there IS a bug on High Sierra (but NOT Catalina) with this. Okay, wow. Sorry about that.
I've gone ahead and logged a bug. I'll raise the priority and note that it's already hit at least two users -- if others want this fixed, voicing a concern on these forums DOES help increase the priority of engineering efforts...
Thanks and, once again, sorry for the mix up,
I usually use the shortcuts in "Layers" panel :
Ctrl as Select All
Ctrl + Shift as Add selection (+)
Ctrl + Alt as Substract selection (-)
Ctrl + Alt + Shift as Xor selection (x)
And the shortcuts with Alt are using "Zooming to Content" (new feature). Two shortcuts are impacted, and it has not to be, or maybe we have enable/disable this in preferences.
There is a new feature where Option (Mac OS) + clicking on a layer thumbnails causes the content of the layer to zoom so it fills the active window.
Option + Command + click on a layer thumbnail should result in the contents of that layer being subtracted from the current selection.
Instead, Option + Command + click on a layer thumbnail causes both actions to occur.
Same is true for Shift + Option + Command + click (intersect selections).
Hopefully this bug will be addressed in the the next update.
Can this be turned off this annoying new feature?
So I have an image of a house on a separate layer, cutout from the background. In front of the house I then have a cutout image of a palm tree on yet another separate layer.
So - 3 layers: 1.Background, 2. house and 3. palm tree.
Lets say that I now want to paint the house blue and still have the palm tree in front of the house in its original colour.
So this is what I do:
1. I make a selection of the house by selecting the layer with the house (so now I have marching ants around the house selection).
2. To subtract the palm tree from this selection I now hold down the Ctrl + Alt keys (on my PC) and click on the small thumbnail image pertaining to the layer with the palm tree...
And this is where it all goes wrong (intermittently 50/50%) - it subtracts the palm tree from the selection as it should - but 50% of the time the view will zoom in on a completely irrelevant area of the image, right down to giant pixels showing - while at the other 50% of the time, it will zoom right down on the palm tree. (Which is actually really annoying too!! - because I have no intention of working on the palm tree. And I am told by Adobe that this stupid auto zooming cannot be switched off in version 2020).
Because of this "...zooming in on a completely irrelevant area of the image, right down to giant pixels showing" I have now had to revert back to Photoshop version 2019 to be able to do my work.
PLEASE Adobe - make version 2020 a functional version.
Traditionally, you ctl+left click on a layer thumbnail to make a [marching ants] selection in the Document window. To add to the [marching ants] selection, say other layers you want to have marching ants to, you hold ctl+shift+left click on those layer thumbnails. So far, so good, right? Those work fine still. HOWEVER: If you want to either use a layer thumbnail to intersect with or subtract from the [marching ants] selection: Say you have a leather jacket on a layer, and above it you have a layer for buttons on the jacket. You want to tint the jacket but not the buttons, on a non-destructive layer that you want placed above all layers. You ctl+left click the jacket layer icon in the layer panel, which results in a marching ants selection. Now you want to remove the buttons from that [marching ants] selection. Traditionally (and we're talking decades, literally, of using Photoshop here- I've been a game dev for 24 years, so believe me when I say this is a new problem) you ctl+alt+left click the THUMBNAIL of the layer in the layer panel. The good news? It still MOSTLY seems to subtract from the [marching ants] selection as intended, but it ZOOMS INTO THE LAYER. This is very jarring, and really wrecks a workflow. Is this making sense? If not, I'll actually construct a GIF so it's finally clear. Nobody in support seems to be getting this, and it's super bizarre that it's getting overlooked so completely. It's also bizarre that so many are griping about it and the devs are parading solutions to a completely unrelated issue. I finally found a workaround, where, after I select a layer, I then right-click a layer thumbnail and choose Add/Subtract/Intersect Transparency Mask.Can devs PRETTY PLEASE make it so we can disable this alt click to zoom in? It's CRAZY annoying and is destroying workflows!!
Give us a checkbox in preferences to turn off alt-click layer zoom to fit?
Alt-clicking layer zoom to fit still conflicts with standard pixel masking shortcuts using the alt key and clicking on layer thumbnail.
This is extremely annoying and haven't been fixed in the last two updates.
Anytime a selection is to be masked using either ctrl+alt (remove layer pixels) or ctrl+shift+alt (mask selection within pixels) it also zooms to fit that layer bounds.
It could be solved by not having alt-clicking to zoom active on layer thumbnails but since its generally annoying to zoom whenever you are one pixel of from clicking a clipping mask it would be best to have the option of disabling it altogether.