Issues with Preview Version 11.0 (1147.1.10) on Golden Gate 27.2

This issue has been reported and linked to a corrupted container cache that sometimes occurs during the macOS Golden Gate 27.2 update. When you multitask or switch windows, the application loses its reference to the active PDFKit framework indexing, causing the search count to display while leaving the sidebar empty and disabling navigation arrows.

The Fix: Clear the Preview Container Cache

Since standard restarts do not clear deep container states, you can resolve this by purging Preview's cached application states and preferences via Terminal. 

• Provide Terminal with Full Disk Access:
  • Go to System Settings > Privacy & Security > Full Disk Access.
  • Toggle the switch next to Terminal to enable it. (Note: Without this step, the cache deletion commands will return an "Operation not permitted" error). 
• Open Terminal (found in Applications > Utilities or via Spotlight).
• Run the following commands one by one, pressing Enter after each:

rm -rf ~/Library/Containers/com.apple.Preview/Data/Library/Caches/
rm -rf ~/Library/Containers/com.apple.Preview/Data/Library/Saved\ Application\ State/
rm -rf ~/Library/Containers/com.apple.Preview/Data/Library/Preferences/
rm -rf ~/Library/Caches/com.apple.Preview/

• Restart your Mac completely

This Quick UI Workaround has also been reported to work

• Go to the View menu in the top menu bar.
• Check if your sidebar is accidentally set to Highlights and Notes.
• Change the view to Thumbnails or Table of Contents. This frequently forces the UI to re-render and populates the search list without needing to restart the app.

Personally, I cannot replicate the issue you describe. Searching in Preview works as expected, initially when a file is opened and after switching to other apps/Spaces.

More info from Apple: Preview User Guide

Since restarting did not help, see if the problem is present when you boot in safe mode. That process performs some system cleanup and clears caches, and also disables 3rd party extensions that may cause problems.

Start up your Mac in safe mode - Apple Support

If that does not correct the issue, test in a new user account. A newly-created user account will have all settings at default, and if the issue does not occur in that new account then it provides guidance on what may need to be changed to correct the issue.

Add a user or group on Mac - Apple Support

Once the testing is complete, the new account can easily be deleted.

Delete a user or group on Mac – Apple Support

Those steps will help to isolate the problem.

It might help to download and run EtreCheck, written by a long-time forum member. The free version is fine. Post the full report using the Additional Text button. No personal information is revealed. 

When I enter a search term then switch windows, then back to Preview, I can continue clicking the arrows to move to highlighted search results further down the document, the sidebar is still there, etc. For example, this is after starting a search and switching to this window:

Then back to Preview and clicking the arrow a few times:

Like you, macOS 27.2 and Preview 11.0 (1147.1.10).

If you cannot resolve, then report a bug to Apple:

Feedback - macOS - Apple

I am using Preview 11 on macOS 27.2. Your third sentence is confusing since I can perform a multi-page search in Preview, with those results displayed in the sidebar, then switch focus to Safari, perform a search there, and then switch focus back to Prevew. The previous Preview search results remain in its sidebar. I can then initiate another search in Preview, with the sidebar populated with the new search results.

If I take your third sentence literally, I cannot reproduce an issue with Preview search here.

I’ve tried everything you’ve suggested, including the Terminal fix, but the issue still persists. It doesn’t happen immediately, which is probably why you’ve had trouble reproducing it. It typically starts after I’ve been working in the app for several minutes, and once it starts, it continues happening. The only temporary solution is to close and restart the app, but the issue eventually returns. It’s become disruptive enough that I’ve had to switch to Adobe to get my work done.