Some M1 Macs Affected By Fast User Switching Screensaver Bug

A growing number of user reports online suggest some of Apple's M1 Mac models are susceptible to a Fast User Switching bug that spontaneously activates the screensaver and leaves the user unable to dismiss it.

macbook pro screensaver table
In macOS Big Sur, Fast User Switching allows users to quickly switch between user accounts without having to completely log out. Based on posts in the MacRumors forums, Apple Community forums, and on Reddit, however, a screensaver can sometimes take over the screen of Apple Silicon Macs without notice, rendering the desktop workspace completely unavailable.

While the screensaver appears on the screen, the mouse pointer is still on top and moving, but nothing else works, and users have to close and re-open the lid on their MacBook Air or MacBook Pro, or light press the Power/Touch ID key or use the Alt-Command-Q key combination to get back to the login page.

MacRumors forum member drmacnut:

Brand new Mac mini M1, 2nd day using it, Big Sur macOS 11.1 (20C69) with screensaver and screen sleep set to 20 mins. I was actively editing some Calendar entries when all of a sudden the same exact thing happened (screensaver on, user locked out). I ended up using Remote Access from my MBP to get in and log out the user on the Mini. The Mac mini then jumped to the login screen and it's working fine again now. Very weird.

Apple Community forums member Squeaks2369:

I am experiencing the same issue. M1 MacBook Air. Big Sur 11.0.1. Happens on two separate user accounts, both with the screensaver disabled. No way to exit the screensaver but to close then open the lid. Happens a few times a day while actively using the computer. Browsing various forums it appears others are having this issue as well.

Video shared by MacRumors forum member dawideksl

Disabling Fast User Switching prevents the issue from happening, but that obviously leaves the login feature inaccessible. Having the screensaver disabled in System Preferences for all users doesn't seem to make a difference either.

The issue has been reported on ‌M1‌ ‌MacBook Air‌, ‌M1‌ 13-inch MacBook Pro, and ‌M1‌ Mac mini models, and occurs on all versions of macOS Big Sur, including the latest 11.1 update. Affected users are advised to submit feedback to Apple to hopefully facilitate a fix.

(Thanks, Chris!)

Related Forum: macOS Big Sur

Top Rated Comments

Carlson-online Avatar
42 months ago
I've had the same issue on the 16" Macbook Pro, so I think it's more likely a big sur bug, than an M1 issue.
Score: 35 Votes (Like | Disagree)
calstanford Avatar
42 months ago
I haven't used a screen'saver' since I've switched to LCD screens 25 years ago. So I haven't noticed.
Score: 12 Votes (Like | Disagree)
skardvin Avatar
42 months ago
No wonder when Craig Federighi opened the M1 MacBook Air to show off the spontaneous wake from sleep that it didn't have this issue...?? he must have had to disable fast user switching first before filming. ?
Score: 10 Votes (Like | Disagree)
eddjedi Avatar
42 months ago
I'm sure they will fix it soon enough, but things like this are why I never jump on major architecture changes immediately. If you depend on your device for work, you need some level of stability. I'm keen to migrate to Apple Silicon, but will probably wait until 'M2'
Score: 9 Votes (Like | Disagree)
cwizou Avatar
42 months ago
Author of a macOS screensaver here (Aerial), since the introduction of Catalina (which changed a lot of things for screensavers), I've had users report that exact kind of issue. In some cases, ScreenSaverEngine (the "app" that hosts the screensaver) will lose focus and you see those exact symptoms.

You will see your mouse pointer when you move it around (it's not supposed to) and few things short of Cmd + Opt + Shift + Esc will work. You can also use mouse gestures like trigger Exposé, which is really weird. During the Big Sur beta, this used to happen fairly often with no obvious cause.

My best assessment of the issue is that usually, another app will steal the focus. Something like the crash report window for some other program that crashed in the background will steal the focus by being put up to front. It's quite possible that fast user switching triggers this loss of focus more often, but I don't think this is either specific to M1 or Big Sur.

Hopefully they will start looking into this !
Score: 7 Votes (Like | Disagree)
Serban55 Avatar
42 months ago

I'm sure they will fix it soon enough, but things like this are why I never jump on major architecture changes immediately. If you depend on your device for work, you need some level of stability. I'm keen to migrate to Apple Silicon, but will probably wait until 'M2'
Its an soft issue not an m1
We had on the 16” mbp also for some weeks now
So if this is not fixed on software level..you will get this with m2 or m30 as well
Score: 5 Votes (Like | Disagree)

Popular Stories

iOS 18 Siri Integrated Feature

iOS 18 Will Add These New Features to Your iPhone

Friday April 12, 2024 11:11 am PDT by
iOS 18 is expected to be the "biggest" update in the iPhone's history. Below, we recap rumored features and changes for the iPhone. iOS 18 is rumored to include new generative AI features for Siri and many apps, and Apple plans to add RCS support to the Messages app for an improved texting experience between iPhones and Android devices. The update is also expected to introduce a more...
iPhone 16 Camera Lozenge 2 Colors

iPhone 16 Plus Rumored to Come in These 7 Colors

Wednesday April 10, 2024 3:52 am PDT by
Apple's iPhone 16 Plus may come in seven colors that either build upon the existing five colors in the standard iPhone 15 lineup or recast them in a new finish, based on a new rumor out of China. According to the Weibo-based leaker Fixed focus digital, Apple's upcoming larger 6.7-inch iPhone 16 Plus model will come in the following colors, compared to the colors currently available for the...
apple silicon feature joeblue

Macs to Get AI-Focused M4 Chips Starting in Late 2024

Thursday April 11, 2024 10:10 am PDT by
Apple will begin updating its Mac lineup with M4 chips in late 2024, according to Bloomberg's Mark Gurman. The M4 chip will be focused on improving performance for artificial intelligence capabilities. Last year, Apple introduced the M3, M3 Pro, and M3 Max chips all at once in October, so it's possible we could see the M4 lineup come during the same time frame. Gurman says that the entire...
top stories 13apr2024

Top Stories: M4 Mac Roadmap Leaked, New iPads in Second Week of May, and More

Saturday April 13, 2024 6:00 am PDT by
Apple's hardware roadmap was in the news this week, with things hopefully firming up for a launch of updated iPad Pro and iPad Air models next month while we look ahead to the other iPad models and a full lineup of M4-based Macs arriving starting later this year. We also heard some fresh rumors about iOS 18, due to be unveiled at WWDC in a couple of months, while we took a look at how things ...
apple tv 4k yellow bg feature

When to Expect a New Apple TV to Launch

Tuesday April 9, 2024 8:30 am PDT by
It has been nearly a year and a half since the current Apple TV was released, so the device is becoming due for a hardware upgrade. Below, we recap rumors about the next Apple TV, including potential features and launch timing. The current model is the third-generation Apple TV 4K, announced in October 2022. Key new features compared to the previous model from 2021 include a faster A15...