MacOS 27 Finder Gliching

No, and that is certainly not expected behavior.

Have you rebooted your Mac? If not, that's the first step. If that does not help, then 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. 

Your best bet is to post that Etrecheck report here, using the "Additional Text" button below.

The fact that the problem occurs even in a new user, but - crucially - NOT in Safe Mode, is a dead giveaway that some third party software modification is involved. You may not see anything untowards in the report, but some of us might. If you are worried about sharing the report, take a look at it yourself. It shows no private information, and even the names of the drives are obfuscated.

Well, it looks like I've gotten things back on a level playing field....

I downloaded and ran the latest EtreCheck and did some legacy/unsigned orphan cleanup deletions to get tuned up for the more interesting (and potentially damaging unintended consequences) of removing third party background process software.

Starting in Safe Boot mode to mitigate the intrusive interruptions, I then deleted all components relating to the TechTool Monitor process which was active and repeatedly crashing in the background. Then, just to be sure, I also deleted all of the components relating to NordVPN (which, although I was no longer using it, STILL had some legacy background processes running).

Re-ran EtreCheck for a fresh report and then restarted normally to find a fully stable and responsive MacOS 27 Golden Gate platform....no more glitches!

Thanks to all who contributed!

Here's that report.

"NordVPN Threat Protection Pro"

"TuxeraNTFSUnmountHelper"

Those jump out as possibly problematic. Commercial VPNs claim to hide your browsing activity from websites, and while that may be true those VPN providers just sell your browsing data to others. They often cause slowness, and can significantly reduce internet speeds, as well. I would not use VPN software unless provided by a school/employer to enable access to internal resources from a remote location

As Luis Sequeira1 states, the fact that your Mac behaves normally in Safe Mode means it's a 3rd party extension that's causing the issue.

I had the same problem and thanks to your mention of Techtool Monitor crashing (I have it); I merely tossed the app to set things right. Thanks for your post and thanks to those who responded!

MacManiac_ wrote:

Well, it looks like I've gotten things back on a level playing field....

I downloaded and ran the latest EtreCheck and did some legacy/unsigned orphan cleanup deletions to get tuned up for the more interesting (and potentially damaging unintended consequences) of removing third party background process software.

Starting in Safe Boot mode to mitigate the intrusive interruptions, I then deleted all components relating to the TechTool Monitor process which was active and repeatedly crashing in the background. Then, just to be sure, I also deleted all of the components relating to NordVPN (which, although I was no longer using it, STILL had some legacy background processes running).

Re-ran EtreCheck for a fresh report and then restarted normally to find a fully stable and responsive MacOS 27 Golden Gate platform....no more glitches!

Thanks to all who contributed!

Here's that report.

<EtreCheck report following repairs.log>

Congratulations for resolving it!

A general comment -- many of the installations listed in the Etrecheck report show installation dates long before Golden Gate was released. You should check for updates in the few weeks leading up to Golden Gate's release as often those are needed for compatibility. There are many installations showing an April 2026 date, and others going back to 2025, 2024, 2023, 2021, 2020 ... and even this one

com.hp.help.tocgenerator.plist (? 11d191c4 - installed 2009-07-28)

No doubt some of these were migrated over from older computers but I can't imagine that all these older apps or extensions are running smoothly under Golden Gate. When I migrate to a new computer I tend touring over only files and accounts but I install all software fresh anew.

Reboot / cold start = no joy....glitch remains constant at about a 10 second recurring interval. When the screen glitches, my typing is interrupted, Excel resets to the active cell and inactivates the search field, the displayed web page in Safari resets to the top of the page, etc. REALLY INTRUSIVE glitch!!!

New clean test User = same result.

The EtreCheck results showed some legacy software existing in Downloads, however, it was not installed / active.

Booting into Safe Mode appears to resolve the glitch, however, I haven't been able to isolate a particular process that was bypassed or suppressed in Safe Mode when compared to those running under a normal boot.

Using Activity Monitor and the Terminal top command are both unsuccessful for isolating the issue.

I'm open to any and all suggestions at this point.

MacManiac_ wrote:

<Etre Check Report.log>

Here's the result from Etre Check...

You used a very old version of EtreCheck which may not be as familiar with more recent changes to macOS. Download the most recent version from here:

https://etrecheck.com/en/index.html

Here's the result from Etre Check...

That's great. Thank you for reporting back with the solution.