Just upgraded to Big Sur and, among other issues, my Windows 10 VM flickers in full screen mode. It did not do this in Catalina using the same version of Fusion.
My system is 2019 15" Macbook Pro i9 with 32GB RAM.
In full screen my display flickers but not in windowed mode. My display is a Dell U3818DW running at 3840X1600. Again this worked yesterday before upgrading to Big Sur.
I tried the workarounds, like trying to disable 3D support or switching the renderer. Unfortunately, dimming & brightening is still there.
PS: I'm sorry, wasn't logged in when posted the answer... Didn't know that works...
Another workaround which seems to do it for most people is having the Full Screen Minibar set to Always Show in the View menu. I think for me I had to reboot before it took effect.
I'm currently working only with the integrated MacBook screen, I only have one color profile, and this is active.
I think the workaround with the full screen minibar set to always show will actually help.
I had to restart / shutdown the Windows VM and I also restarted my Macbook, and until yet it seems that there is no flickering. Weird.
Same here unfortunately.
As mentioned in a comment below, the problem was rectified by disabling Nightshift so perhaps macOS is trying to apply dark mode or something? Not sure but my fans are screaming and this Radeon setup is killing me softly.
The full screen minibar workaround has been reliable for me for quite some time now.
I normally work with my VM on an external monitor. This might help someone... Yesterday, the annoying flicker returned (which does appear to be an intermittent cycling change in colour & brightness), and the minibar was not showing for som reason. Changing the menu setting back and forth so that the minibar should always appear, or show in a different location on the screen did not persuade it to reappear, and the flicker continued. It wasn’t until I moved the mouse pointer from the external monitor to the laptop display and clicked there that the minibar suddenly returned, and the flicker was gone.
I'm also affected by this bug. I'm on 2018 Macbook Pro, latest big sur 11.1 and VM on latest hardware version.
Enabling full screen mini bar overlay fixes it or disabling night shift schedule in Mac OS settings.
I have a 2019 16 inches model and was having problems with the external Acer display (flashing and flickering) but the problem was using an external USB-C hub from Satechi with an HDMI port. After I changed the connection to a direct USB-C-HDMI cable the display problems went away. Are you seeing the problem only when using Fusion or does it also happen with other heavy tasks?
I resolved the same issue with my external Dell U2715H monitor by selecting Mac OS-->System Preferences-->Display and then select Color-->Calibrate... for the Dell monitor.
I'm running Fusion 12.1 on Big Sur and Windows 10 as guest OS.
Spot on Jonathan, worked perfectly; flickering gone, thank you! Actually the minibar when dragged to the top of the screen is also quite useful indeed! This is of course a workaround and hopefully the VMWare team will include a proper fix soon.
Same issue here gets resolved by always displaying the minibar, but would love a true fix. Bummer that I paid to upgrade in order to keep working with VMs on Big Sur just to have this bug be such a nuisance.
This is happening on my built in display as well as on an LG Monitor