How to restore precise text selection in Preview after macOS Tahoe update?

Ok.

Have a nice day.

For what it's worth, the issue isn't just with Preview. It's also an issue with Skim & PDFgear. Probably others as well.

Nicholas Baker wrote:

I had hoped that the recent update to Tahoe 26.1 would have fixed the text-selection issue with Apple Preview but, sadly, it's still the same problem. Let me explain: prior to the Tahoe "upgrade"

What do you mean "prior to"? You only referenced Tahoe 26.1. Are you saying that Tahoe behaves differently than Sequoia? Or Snow Leopard?

place my cursor where the selection began and drag it to the end. The selection would highlight in blue allowing me to inspect the range of my selection and then make the copy.

What do you mean "make the copy". Are you performing the copy command from the File menu? Or are you using the command key? Or are you trying to drag and drop? Or something else?

Since the "upgrade" that's not how text selection from PDFs in Preview works. The selected text disappears as one drags the cursor over it. One has to "click" out of Preview in order to go back and see the selection blacked out (for want of another description)before adding the copy command.

I can't reproduce what you're seeing. No text or selection highlight disappears. I tried it on Sequoia and it behaved identically there.

I have seen a couple of people talk about some kind of colour, contrast, or brightness problem where certain colours or shades of colour are indistinguishable from white. That sounds more like what you're describing. When you click outside of the active Preview window, the window will go inactive and the highlight colour will change from the accent colour to a grey colour.

I don't know what's causing this, but it's definitely some display issue. Do you have any custom colour adjustments in System Settings > Displays? Have you changed any defaults in System Settings > Accessibility?

One easy test is to create a new user account. Copy a problematic PDF to /Users/Shared and then open it in the new account. It should work normally there. If you can identify what's different about the settings in your primary account compared to the new one, then you can correct it. If it looks the same in the new account, then the change it being applied on a system level, not on an individual user level. For example, if you have an external display, you could cause this by misconfiguring the colour adjustments.

Nicholas Baker wrote:

Let me show you a small movie of how it looks for me...

Your video is about what I was expecting to see. Compare this to how it looks for me...

Active selection:

If I make another window active, it looks like this:

In your video, the inactive highlight is much darker. This suggests a problem with brightness and/or contrast. That could make the light blue disappear completely and make the light grey much darker.

Once again, just clumsy and un-Apple like.

The first step to fixing the problem is identifying where it is. It's not Cupertino, it's your desk.