macOS Big Sur - Multiple Display "Recovery"

Same issue here. It happened when upgrading to Catalina a couple of years ago. The issue disappeared after several upgrades though.
Now it is back again on Big Sur :(

My issue that started with the BigSur update is that when I'm working on my macbook directly and then plug my external monitor, one or more of my apps remains open but mostly invisible. I can swipe up with 3 fingers and see all the apps, but when I choose one I cannot see it - even if it is the active software.

running a 2019 macbook and external monitor is not being recognized.

using a dell monitor, running usb-c to displayport cable. any ideas?

Same issue for me. Extended monitors no longer keep the apps in place once disconnected from the macbook pro late 2016.
Please fix asap.

Same here. Even after wake from sleep the apps on the second monitor are hidden. I only can access the app windows by showing all open apps, then move the app to the internal display, and after restoring it, move it back to the second display.
Looks like Apple never tested with multiple screens.

same issue on 2019 macbook
My external LG monitor is not being recognized. 

I have the same problem. My LG monitor is permanently connected to my MacBook. When my screen is locked and I unlock it using my fingerprint, some windows (e.g., Mail, Finder and Safari) are not visible. For other applications (e.g., Slack) it works. It seems that the applications that were shown on the external monitor because the screen was locked "loose" their position. The ones that were shown on the MacBook display keep their position.

I need to use the Magnet tool to move the windows in order to make them visible. This was definitely not he case before upgrading to Big Sur.

This new behaviour is quite annoying - in particular if one needs to unlock the screen multiple times a day.

Similar problem...Big Sur, Mac Mini 2018 with two (2) LG 27" 4K monitors. I can only get one monitor to work at a time. I've tried a dual monitor configuration using USB-C connections for both and USB-C for one monitor and HDMI for the other. I've tried Detect Displays to no avail.

I had a similar issue with Catalina, but only at startup. If the 2nd monitor wasn't recognized, shutting down and restarting resolved the issue.

I had this issue as well, both in public beta and now in the public release.

Fix for me was to reset NVRAM and SMC, immediately solved the problem. Am back to my normal workflow, able to leave my desk to work on the laptop then go back later. The external display shows all windows as they were before I unplugged.

NVRAM Reset: https://support.apple.com/en-us/HT204063
SMC Reset: https://support.apple.com/en-us/HT201295

Hope it helps others as well. 👍

Same - was fine using LG 4k wide monitor until plugged ipad into USB c connected to external monitor. Selected to change the input accidentally to the Ipad and when switched back everything was gone.

Had to connect back to usb c to ipad, unplug connection and reset input to hdmi before it 'rediscovered'

I can’t connect my 2018 MacBook Pro via HDMI to any of my TVs anymore. Very frustrating! It doesn’t even register that anything is plugged in.

I have a new MacBook Air I bought earlier in the summer, and it used to be able to connect to a TV monitor with an adapter and HDMI cable. After the upgrade to Big Sur, I get nothing. It will not find the display, and it is super frustrating. I need a fix.

Same exact issue, I have 2 external monitors with my iMac and I use all 3 screens simultaneously. I Day trade so I have me Set up saved to go to all screens as I need it when I log into the trading platform. It was working fine until the Big Sur update. Now only my Mac screens shows and the windows that should be on the other monitors just minimize into one small tab behind my Mac screen. So every morning or everytime I log back into the platform I have to manually move everything back to it's correct place and size. VERY FREAKING FRUSTRATING!

As a workaround, until apple resolves this fundamental issue.

I open System Preferences > Display

Then when the option presents itself on the second screen, I choose between scaled and one of the options and it brings the windows back. then I default to what setting was there before.

This is of course a pain because every time you lock the laptop, the windows gets hidden when unlocked again.

Upgraded to Big Sur connected my external monitor to my 2018 MacBook Pro via HDMI and doesn't recognize my Benq GL2460 Monitor.

It doesn’t even register that anything is plugged in...Rebooted,Plugged and unplugged monitor...Still doesnt work.

Has anyone figured this out....My workflow is garbage...I cant

I've also been having issues since the update. At first there was a lot of glitching out but now that the update has settled I only have one problem. If I have my MacBook HDMI connected to my monitor with different windows open on either one and then my computer goes to sleep, when I wake it up again the ones on the monitor are gone and only the main window I was using is open on my laptop. When I do the three finger swipe up to look at all my open tabs, they reappear as open on the second monitor but if I click on them it goes to the screen with no windows. This is the main problem I have right now.

I've also had a problem where it'll only allow me to have one application on either screen at a time. For example, I always work with Spotify, Safari, and Premiere open at the same time, with Premiere on my laptop and the other two on the monitor. It would only let me have one of the three opened, as soon as I would open up the other it would immediately hide whatever I was last on. This problem occurred more so only at the beginning after the update happened.

Third issue I've noticed is that sometimes when I have numerous windows pulled up between monitors, if I click on the Home Screen (outside of any window), it'll close the last one that I was using. Very weird stuff and also extremely annoying making it impossible to be productive. This issue also happened more so only at the beginning of the update.

Solutions: At the very beginning of experiencing these issues I either had to restart/shut down my computer to fix it or unplug the HDMI and replug it in. Now, I've found that when it goes to sleep and all of the windows close except the main one, I just have to minimize that window and the rest show up behind it. I still have to drag them over to the monitor which is super annoying though. But this only happens when the screens go to sleep after a few minutes of inactivity. So it's not as big of an issue as it was right when the update took place. But it still isn't near-flawless like it was pre-update.

Same behavior on a 2018 15-inch MacBook Pro, and an external LG Full-HD Ultrawide monitor. I don't even need to unplug the second monitor, the computer sleeping is enough to make all workspaces on the second monitor empty and the windows to hide. Frustrating, this never happened on Catalina.

Just upgraded to Big Sur (11.0.1) on a 2018 MacBook Air (retina). I use two external displays through a MediaGear DisplayLink Dual 4K Display monitor hub. Neither external display will now work (both did under 10.15) - they do not show up in the Monitor system panel and they stay blank (no flickering, anything).

The monitors are old, and I'm using VGA to HDMI conversion cables to plug into the MediaLink hub. If I plug in the monitors directly into the MacBook Air through an Apple HDMI to USB-C adapator, one then will now work (a Dell 17") but he other (a Zalmon Trimon 3D) does not. I've tried NVRAM and SMC resets to no avail.

This is a pretty serious problem. I could buy a new monitor, but this seems extreme when it's clearly an issue from upgrading to Big Sur. Also, how can I be sure that a new monitor will work any better?

Advice welcome. I am submitting a bug report as well.

Same issue.

Same issue here.

I'm using LG 27inch for 27inch iMac 5K with Thunderbolt to HDMI conversion
After waking up from sleep, the iMac shows the LG display app window for a moment, then after the LG display is activated, the app window does not appear.
Start "System Preferences"> "Display", and once you change the resolution on the LG display, it will be displayed, so you can use it by restoring it again.

I FINALLY GOT IT TO WORK!!!!

Issue:

• My external Monitor stopped working after upgrading to BIG SUR.

Computer Setup:
I have a usb-c adapter connected which allows my external monitor , network, and I plugged my power in usb adapter and speaker to connect...


Fix that worked for me:

1. I first unplugged adapter

2. unplug power from adapter

3. reconnect adapt WITHOUT (Usb-c )power connected...FINALLY External monitor was found and displayed

4. Then plugged in usb-c Power to adapter

Possible Explanation:
Some drivers might no be loading via adapters when Power is connected to it. Basically reconnect everything without power and then connect power to adapters...

Personal Commentary:
I hope this helps someone....I've been fighting with this mess for 2 days now....APPLE needs to get their act together.
This was some old WINDOWS OS BS!!....That why I left Windows....

Where is Steve Job...he would have NEVER allowed THIS to happen to mac users....EXTERNAL MONITOR NOT WORKING???

I'm having essentially the same problem. When I have app windows on an external display, then put the mac to sleep, and then wake it up again, the windows that were on the external display have shifted off of that display into an area outside of that display's viewable area (in my case, as though I had drug them off the screen to the left until they are completely off the screen. They are not, however, back on my Mac's display. To be able to see them or interact at all, I have to open mission control, drag them from the external monitor to the Mac's monitor, close mission control, and then drag them back to the external display.

None of this was a problem before upgrading to Big Sur.

How does one file a bug report?

Same problem with second screen here. Used to work fine but now, even though I can call up both screens, if I put the main computer to sleep the second screen (another, older imac) will wake up shortly after showing its own desktop. When I switch back to 2 monitors I find any of the windows that were open on the second screen 'lost in the wilderness' and unable to be recalled.. its a pain in the backside.

same problem