macOS Big Sur - Multiple Display "Recovery"

App & System Services Core OS macOS

Created Jun ’20

Replies 163

Boosts 0

Views 52k

Participants 153

I've found something thing macOS Big Sur broke - the "recovery" after changing display sources. Let me explain...

I have one big 4K monitor, connected to both my Mac (USB-C) and my PC (HDMI). I switch between the two sources on the monitor depending on what I'm doing. Each computer also has its own dedicated monitor (built-in for my Macbook, an old external for my PC).

Prior to macOS Big Sur, if I switched to the PC input on the monitor, all the macOS windows would shift over to the built-in laptop display, and then shift back to their correct window once I switched back. They no longer do that.

The application all stay on the laptop screen and the big screen is empty when I switch the source back on the monitor. I then have to move everything back to the big display.

I guess that's better than the PC behavior where even if you switch the source on the display back to the Mac, Windows still thinks its connected and continues to extend the display (the fix for that is to go to display properties and select "only show on display 2") , but thats a whole other gripe.

Has anyone else experienced this as well? Is there a setting I'm missing? Should I file a bug report?

Boost

Bostheatre OP

Nov ’20

UPDATE: 9:21 EST - Working now.....

Same issue. Running two monitors. USC C-HDMI working, mac mini 2018 HDMI not working. please fix before monday, need second monitor and dont want to have to buy another usb c-hdmi

CrispyCritterz OP

Nov ’20

With the new Big Sur update, my iMac’s secondary monitor hooked up through USB-C to HDMI adapter stopped working. I was able to get the monitor on by using mirror screen, but I cannot use as an extended desktop. All beta versions leading to the latest version worked without issue. This should be worked out before final release.

TheSteve OP

Nov ’20

I have a Mac Mini 2018 with two monitors. After upgrading to Big Sur the monitor plugged in with a USB C to HDMI converter was recognized, but the one plugged directly into the HDMI port wasn't. Turning the computer off completely and then restarting fixes the problem for me, but it's happened a couple of times now and is really annoying.

ctpiccone18 OP

Nov ’20

I am having the same issue, wish I never updated this early. It seems like most people are having issues with HDMI, my display cord is a usb-c to usb-c and its still not working. It seems now the only solution is downgrading to catalina...

glynmaclean OP

Nov ’20

I have two 4K monitors that worked seamless prior to Big Sur. One has stopped working altogether with no apparent settings to reinstate the monitor. I have the highest end Macbook Pro on the market, so graphics card isn't the issue. I'm on MacBook Pro 16-inch 2009, 2.4 GHz intel 8 core i9 with 64gb 2667 MHz DDR4 ram and AMD Radeon Pro 5600M 8 GB graphics card with 8 TB SSD hard drive. Which is the top configuration. There are four Thunderbolt3 ports, designed for 4K power. I am using two for 4K monitors, 1 for hub and 1 for external hard drive. It seems to me this is a driver issue around batter power regulation that is defaulting to turn off the additional 4K monitor. I can't find a solution to this online yet and this has interrupted my workflows. Very annoying since I paid so much for the highest spec machine.

adanprados OP

Nov ’20

i had the same problem with my monitor external, plss apple help us

roadtoad2020 OP

Nov ’20

Same issue here. 2019 MacBook Pro attached to an external display (USB-C to HDMI).

All the windows are visible in Mission Control but I can't access them unless I unplug my external display and then they show up on my laptop display.

ksemuldie OP

Nov ’20

Same here, very annoying.

2019 MacBook Pro attached to an external display (USB-C to HDMI).

phishman9 OP

Nov ’20

Same issue with a 2019 MBP, USB-C to USB-C 4k monitor.

The issue can be temporarily fixed by mirroring the display in settings and then turning mirroring back off. This works until I switch the display or the laptop sleeps...sigh.

mabaeyens OP

Nov ’20

Same with MBP 16" 2019. Working just fine with the latest Catalina as far as I can remember.

The external LG (HDMI to USB-C or HDMI to Hub via USB-C) works fine after reboot, when computer sleeps and wakes up, it blinks a couple of times, then switches off. The open windows remain on the external display although it's off, and there's no way to turn back on the LG unless I reboot the Mac

NINJA_TAC0 OP

Nov ’20

Same issue. Using MacBook Pro 13" Late 2013. Close laptop itself and use two monitors for display. One monitor is thunderbolt 2 to HDMI and displays fine post upgrading from Catalina to Big Sur. The other monitor is just HDMI and is now a smaller display size despite saying 1920x1200 I have black bars on top/bottom/left/right. I restarted manually and it didn't work. I restarted with just the 2nd monitor connected (the one with black bars) and it loads full screen as it is supposed to. The second I plug in the second monitor, my mac restarts and says it ran into an error. After restarted, same situation.

chinonk OP

Nov ’20

I got same issue, but already fixed by installing DisplayLink Manager Graphics Connectivity. I am using ASUS USB external monitor.
When the application installed, Allow the DisplayLink Manager on Security & Privacy - Privacy tab - Screen Recording section.

abvijay OP

Nov ’20

Even I am facing the same problem,when I connect external monitoprs, it seems ot show, but in few seconds all monitors don't get signals..its is frustrating

In generall I have been having a lot of issues with Big Sur upgrade...I have MBP2019
1) Very slow booting
2) TouchID not working (insipte of resetting SMC)
3) external monitors not working
4) the system goes to zombie mode for sometime, and doesn't respond

I regret for upgrading, I lost 4 days of work because of this!!! loosing respect for apple. Moved back to Windows to continue with my work

ValBap OP

Nov ’20

Same here with my 3 external monitors:

1 USB-C to HDMI
1 USB-C to HDMI
1 adapter USB-C to HDMI + cable HDMI (Not working).

Everything was fine till the update.
Now I get this "USB accessories deactivated" as soon as I plug the HDMI, even if alone.

ejamartins OP

Nov ’20

I have two DELL P2414H Monitors, and after the update of my Mac 2019 for Big Sur version, one of the monitors are flickering. Never had a problem when using Catalina.
Basically, I have a docking station from Thinkpad and one of the monitors is connected to it and connects to my MacPro with USB-c and the other I am using a display port adapter and connected directly to my Mac. The monitor using USB-c is flickering after the update.

ejamartins OP

Nov ’20

CrispyCritterz OP

Nov ’20

UPDATE

got my monitor working. Go to the settings menu and open “displays”. Use “gather windows” button on the screen. This will bring your external monitor settings forward. Change your resolution and refresh rate for your external monitor. After about 5 seconds, my external display came back to life!

krizzli OP

Nov ’20

I have the same issue as @romankk where, even worse than what OP describes, my windows are somewhere off-screen when I plug back in my external monitor after disconnecting it. I can't drag them, I can only send them to the MacBook Pro Desktop through Mission Control and then they are somewhat visible (usually an edge of the window is visible).

romankk OP

Nov ’20

I found another, quicker way to recover the apps on my main screen.
In the system settings, change the main monitor to the other screen back to the original screen. Suddenly, the apps appear again.

Zman8 OP

Nov ’20

This is still happening in the GM release...

Rudy63 OP

Nov ’20

Just upgraded to Big Sur and found only one monitor is supported anymore. Catalina and all previous OS versions worked fine.
I wonder why Apple is not catching such a big problem in their release testing process.
Very frustrating.
Should switch back to Windows.

rbalthazar OP

Nov ’20

A quick workaround for windows to switch back to the correct monitor when disconnecting the second monitor and connecting it back.
If you minimize all windows (Option+Command+H+M) before connecting back the second monitor, windows will be in the same monitor they were previously when you click in their dock's icons.

rajivrajaniipy OP

Nov ’20

I also have same issue, have LG 4k monitor, whenever my MacBook goes to sleep and I wake it up all my apps go to inbuilt screen, didn't use to happen before the upgrade. now its a pain to manually move all the windows back to monitor every time I start to use it after it sleeps!

cherokee1 OP

Nov ’20

Same issue with 2019 iMac and LG 4k monitor.

Similar to @rajivrajaniipy, on wakeup from sleep, my external monitor is blank, and windows from that monitor are hidden and not accessible. Even when the external monitor is working, the desktop is not accessible on that screen.

chuckyoufarley OP

Nov ’20

Similar problem here after upgrading to Big Sur yesterday. If I switch my monitor input and switch back to the input my 2018 MacBook Pro is on then all my windows are hidden off screen.