Menu bar issues OS27

Go to System Settings > Menu Bar, set the Automatically hide and show the menu bar popup menu to Never (or On Desktop Only).

More info: Change Menu Bar settings on Mac – Apple Support

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. 

I cannot personally replicate this issue. With the setting above on Never (my usual choice), in full screen apps the Menu Bar remains (the screenshot below is on my 5K:2K external display, but the same is true on the internal display).

I solved this issue with OS 27 (27.2) on my MacBook Air 13-inch M4 2025.

Issue: Since upgrading to OS 27 (no issues on 26.x), if I use a photograph from Photos (a picture I had taken with my iPhone) as my wallpaper, the menu bar disappears in certain situations, for example when I open Safari (the menu bar completely disappears, or flickers in and out, unless I click where the menu bar should be. It will reappear if I click it or reopen Safari, only to disappear again).

Solution: Use the built-in wallpapers, or, go into the wallpaper section of Settings and select a new image (NOT a photograph from Photos, but a wallpaper image I downloaded from the internet). Using either an Apple wallpaper or any image from my Pictures folder (NOT from Photos) solved the issue entirely.

This is only a work-around, as I love taking photographs and using them as my Macbook's wallpaper.

I'm having the same issue, but wanted to share that my solution was to Force Quit the process called "MenuBarAgent" in the Activity Monitor app. That worked for me!

While several people are seeing this, many more are not.

This suggests that there may be something causing this problem, and not merely a bug in macOS 27.

Can you test to see if the same menu bar problem occurs in Safe Mode?

If not, then it would confirm that some third party software modification is at play.

UPDATE: After playing around with this for a few days, I found that if you make your photograph your background using the Wallpaper settings (in System Settings), the issue does not occur. The missing Menu Bar therefore only seems to be happening to me if I make a photograph my wallpaper via the actual Photos App itself. If that makes sense. :)

I started having this issue with the 27.2 update. After a period of a minute or so, the menu bar would disappear. I have System Settings 'Hide/Show menu bar' set to 'Never', but still this behavior occurred.

In my case I could click on the Desktop with my mouse and the menu bar would reappear.

I did find that opening Activity Monitor and finding the MenuBarAgent process and selecting it, and then clicking the X to stop the process and force a reload seemed to make it quit this for a while. Anyway - this is a bug among many with Mac OS 27.

Update: I thought 27.0.1 might resolve my issue of "menu bar disappears upon waking from Sleep." It did not.

I tried all the previous suggestions, which did not work.

My logic (such as it is) and intuition (such as that is) suggested maybe I should switch out my Desktop wallpaper and see if the background image effects the menu bar.

For years I used Apple's shot of Catalina Island at sunset because I loved the image. But just for fun, let's change it to something new: Golden Gate at Night.

Voila! Or as Al Bundy said on "Married With Children", "Viola!" The issue is resolved. I can put the Mac to sleep and when it wakes the menu bar is exactly as it should be.

Magic -- and sometimes just plain "stuff" -- happens.

I'm not saying this would work for everyone but it's worth a try. Nothing ventured, nothing gained.

JG

Continues to happen for me usually after my iMac sleeps overnight. I wake it and there is no menu bar. I get it back (as someone else suggested) by clicking on any app in the dock. Even now with the 27.0.1 update.

Changing the wallpaper from my previous slide show to the generic Dynamic Golden Gate screen saver seems to have solved the issue on this MacBook M4 Max. (BTW: none of the instructions for switching the reboot to Safe Mode seemed to work for this OS, despite numerous attempts.)

I noticed this problem right away after updating. My solution wants to hit the escape key and an exit full screen for me. I think this is a really screwed up thing to mess up on an update. Just figured I'd post this you can try it and see if it works for you. I want them to fix it.

Me too. Tried the steps recommended by neuroanatomist but the issue persists.

My workaround: click on an icon to open an app. Then everything is fine .... until it's not. Usually occurs upon waking from Sleep.

Not a big problem, just a "problito." Definitely incorrect behavior.

Reported it to Apple.

MacStudio M2

Golden Gate OS27

Same problem. Even if auto hide of Menu is set to Never. Also, the menu bar was not there after my iMac was left sleeping over night. Had to restart to get Menu Bar back. So, looks like there is a bug to me.

This worked for me too.

My issue was that the menu bar would stay visible even when in full screen mode, despite being set to hide in full screen only. Killing the "MenuBarAgent" agent fixed it immediately.

I have not seen the issue for a few days now and have my wallpaper set to change every 12 hours. Perhaps some of them are problematic with the menu bar as you are showing.