Ive had my M1 since release (Pro), and I have yet to experience a single bug. Pretty smooth rollout to be honest. This will be updated soon I am sure.
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Some M1 Macs Affected By Fast User Switching Screensaver Bug
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Here's the fix for the problem that worked for me:
https://discussions.apple.com/thread/252083925?answerId=254205721022#254205721022
"Configure the screen saver to not be displayed on the login window, which will also prevent the screen saver from starting 20 minutes after clicking on Login Window… or Switch User. This can be done by logging in as an admin user and entering the following command into Terminal: sudo defaults write /Library/Preferences/com.apple.screensaver loginWindowIdleTime 0 When the Password: prompt appears, type the password of the user that is currently logged in and press Return (the password being typed at this prompt will not be displayed)."
For the nerds:
jan@canephora ~ % ps -A | grep Screen
(some stuff cut)
10999 ?? 0:30.41 /System/Library/CoreServices/ScreenSaverEngine.app/Contents/MacOS/ScreenSaverEngine -loginWindow
11002 ?? 0:00.04 /System/Library/Frameworks/ScreenSaver.framework/PlugIns/Computer Name.appex/Contents/MacOS/Computer Name
11003 ?? 0:00.05 /System/Library/Frameworks/ScreenSaver.framework/PlugIns/iLifeSlideshows.appex/Contents/MacOS/iLifeSlideshows
11004 ?? 0:00.10 /System/Library/Frameworks/ScreenSaver.framework/PlugIns/legacyScreenSaver-x86_64.appex/Contents/MacOS/legacyScreenSaver-x86_64
11005 ?? 0:00.04 /System/Library/Frameworks/ScreenSaver.framework/PlugIns/legacyScreenSaver.appex/Contents/MacOS/legacyScreenSaver
11197 ttys002 0:00.00 grep Screen
jan@canephora ~ % sudo kill -9 10999
First, you can try killing the process and then re-HUPping the windowserver. But also, note that the ScreenSaverEngine is being started with the -loginWindow parameter. I'm thinking something weird happens and the system believes that the login screen is active but hasn't seen any input in a while and tries to put the display to sleep.
https://discussions.apple.com/thread/252083925?answerId=254205721022#254205721022
"Configure the screen saver to not be displayed on the login window, which will also prevent the screen saver from starting 20 minutes after clicking on Login Window… or Switch User. This can be done by logging in as an admin user and entering the following command into Terminal: sudo defaults write /Library/Preferences/com.apple.screensaver loginWindowIdleTime 0 When the Password: prompt appears, type the password of the user that is currently logged in and press Return (the password being typed at this prompt will not be displayed)."
For the nerds:
jan@canephora ~ % ps -A | grep Screen
(some stuff cut)
10999 ?? 0:30.41 /System/Library/CoreServices/ScreenSaverEngine.app/Contents/MacOS/ScreenSaverEngine -loginWindow
11002 ?? 0:00.04 /System/Library/Frameworks/ScreenSaver.framework/PlugIns/Computer Name.appex/Contents/MacOS/Computer Name
11003 ?? 0:00.05 /System/Library/Frameworks/ScreenSaver.framework/PlugIns/iLifeSlideshows.appex/Contents/MacOS/iLifeSlideshows
11004 ?? 0:00.10 /System/Library/Frameworks/ScreenSaver.framework/PlugIns/legacyScreenSaver-x86_64.appex/Contents/MacOS/legacyScreenSaver-x86_64
11005 ?? 0:00.04 /System/Library/Frameworks/ScreenSaver.framework/PlugIns/legacyScreenSaver.appex/Contents/MacOS/legacyScreenSaver
11197 ttys002 0:00.00 grep Screen
jan@canephora ~ % sudo kill -9 10999
First, you can try killing the process and then re-HUPping the windowserver. But also, note that the ScreenSaverEngine is being started with the -loginWindow parameter. I'm thinking something weird happens and the system believes that the login screen is active but hasn't seen any input in a while and tries to put the display to sleep.
Yep, I’ve been having the issue on my M1 MacBook Air. I definitely have the issue more frequently (maybe once an hour) when I’ve not shut down in the last 24h. I filled out a bug report to Apple. Glad this is being reported on - hopefully it’ll push for a quick fix! I should note, other than this my M1 has been a solid purchase.
I blame yearly OS updates. I remember years ago people complaining about Adobe yearly updates and saying eighteen months to two years was a more reasonable new release schedule.
Ugh. I never buy 1st gen Apple products. Wait for them to work the bugs out. Remember the *amazing* 2016 MBP with Touchbar and butterfly keyboard? I'm still typing on it. 
Rev A issues, perhaps. I hope they're able to get the M series bugs worked out by the time they release a new 16 in Pro....
I don't even remember there's a screensaver feature for my Mac. never used that for such a long time. my screen just goes black when it's idle.
I had this issue on my wife's new MBA the other day. It can't be dismissed by any key input but close the lid down then resume dismissed it. Wife freaked out though.
I pushed my wife to give up her Intel MBA for the M1 version. Everytime a bug like this happen, my reputation is fading away.
So far, I had to deal with Google drive not working, Microsoft M1 version crash, and this.
She does enjoy the quietness without the fan, and very long-lasting battery life.
I pushed my wife to give up her Intel MBA for the M1 version. Everytime a bug like this happen, my reputation is fading away.
So far, I had to deal with Google drive not working, Microsoft M1 version crash, and this.
She does enjoy the quietness without the fan, and very long-lasting battery life.
Happened about 3 times. Most recently I was able to stab random keys and avoid a force restart.
hopefully this and all the other M1 bugs will be fixed soon. Having to restart a lot at the moment. Even with Intel macs, I would go weeks and weeks without a restart.
hopefully this and all the other M1 bugs will be fixed soon. Having to restart a lot at the moment. Even with Intel macs, I would go weeks and weeks without a restart.
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 !
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 !
Not for me. This even happens to me while I’m actively typing. I obviously have the screen saver switched off. Real weird...
M1 MBA here.
Noticed on my MBP 2015 with Big Sur that my screensaver (Music library album art) cannot be dismissed by keypress. I have to start banging on many keys for a while and maybe it goes to the login screen, maybe not. This would explain it.
