Windows constantly lose focus on Tahoe

I have the same issue on M4 Pro 24GB.

The fix for me was to disable Forti client from App Background Activity in Login Items & Extensions:

I also found this blogpost about bluetooth devices if it helps:

https://medium.com/macoclock/mac-window-focus-bug-dc5211ce570c

Kms10 wrote:

All apps, even System preferences and top menu bar behave like this. Only spotlight does not lose focus.

I restarted/rebooted my computer more than once -- this issue persists.

I turned off all bells and whistles -- no effect.

I would reinstall the macOS on top of your existing macOS to sort upgrade anomalies.

How to reinstall macOS

Recovery (both M1/M2/M3/M4 and Intel) — How to reinstall macOS - Apple Support

and compare your results.

My first try, see below, using CleanMyMac only worked temporarily. Further search of the background apps (SystemSettings>Login Items & Extensions) showed an app that I thought I had deleted long ago. Turning that off solved the problem: it has not recurred so far -- a week later.

Tip: To investigate which app causes the issue I would recommend to disable all App Background Activity than slowly turn them on one by one.

Kms10 wrote:

When I open any window (even top menu bar) it loses its focus (in case of menu bar it just closes) after some time (random). I cannot use anything with text input for example, because focus is switched randomly when I type something in.

This is a very major issue for me, because my computer is literally unusable right now.

Have you shut down and restarted more than once since your upgrade to Tahoe...(?)

What apps exactly you do not say.

Try quitting the problem app and relaunch it holding the Shift key down and compare your results.

View open windows and spaces in Mission Control on Mac

try turning off the bells and whistle here and get back to terra firma, and compare your results

.

You can alwys Call Customer Support (800) MY–APPLE (800–692–7753)

or on line https://getsupport.apple.com/

or call AppleCare Support at 1-800-APLCARE (800-275-2273)

Outside the USA—Contact Apple for support and service by phone

See a list of Apple phone numbers around the world.

Contact Apple Support - Apple Support

I have another solution. Use CleanMyMac to rid your Mac of accumulated junk and detritus. Then Shut Down (not just Restart) the Mac. That worked for me.

Im not sure how to reproduce, but I have a ticket open with Apple. Currently running in safe mode to see if it manifests in this mode... Hopefully enough stuff will work for e to be productive this way

Maybe we can compare addins

I run Battery magic, bartender, better snap tool, one drive ... I think thats most of it.

I have the exact same issue across all software, including finder

Frustrating as **** as I cant use my mac at all

I agree - I'm loosing focus while typing OR pasting text from an app to another. This a very anoying issue. PLease considere it quickly.