Screen flickering after updating to Mac OS Tahoe

I have a similar setup:

Mac Mini M4 Pro with a Dell monitor.

I'd like to share how I fixed the flickering issue.

The flickering is acknowledged by Dell and other vendors like BenQ—even with newer monitors—as something they cannot resolve on their end.

The root cause is Apple's display controller, which applies temporal dithering by default to simulate smoother gradients, even on high-quality monitors. This causes not only discomfort for sensitive users but also severe flickering in some setups, leading to eye strain and usability issues. macOS offers no built-in way to disable it permanently. That would be very nice if Apple would implement this feature.

The solution:

To disable dithering permanently on a Mac Mini M4, you can use a tool like Stillcolor to override the display controller's default behavior and set it to launch at login. Without third-party tools, macOS does not offer a built-in method to persistently disable dithering across reboots.

I have installed the tool with brew. Have a good day.

[Edited by Moderator]

I had this issue with an Apple Studio Display connected to a 2021 M1 Pro MacBook Pro via a Thunderbolt cable. This was mainly between switching applications or most severely during conversation switching in Messages. I noticed that this got worse with backgrounds set up for contacts.

To resolve I switched from 2048 x 1152 to the default 2560 x 1440. I imagine since it's using a fixed refresh rate rather than the variable one used at the scaled resolution? There might be a better fix, but that's the easiest one I came up with.

Cheers

Critchlowr wrote:

To resolve I switched from 2048 x 1152 to the default 2560 x 1440.

I imagine since it's using a fixed refresh rate rather than the variable one used at the scaled resolution? There might be a better fix, but that's the easiest one I came up with.

Good computing Critchlowr !

I have MBP 2019. I changed Display refresh rate from 60Hz to 59.94Hz. Flickering has stopped.

so glad I'm not the only one. Before updating to Tahoe, I never had an issue once. Im on the M4 MacBook Air. Since I've updated, my display started doing this flickering or as I call it, "Blinking" as if it's trying to auto adjust the brightness. Turned off True Tone, auto brightness, etc. Nothing works, and this came from apple support. I think it's a bug and it's getting really annoying to look at.

I have this issue with an M1 MacBook Pro and Studio Display. I tried section77's solution, which is to install and use Stillcolor, and that worked. If you have Homebrew installed, you can install it via CLI using this command:

brew install --cask stillcolor

It installs it in the Applications folder. When you run it, it appears in the menu, and these settings fixed it for me.

[Edited by Moderator]

Same here. My company issued MBP M4 Pro, my personal Mac Mini M2 and M4 all have the flickering issue (USB-C connection to external monitor) after upgraded to Tahoe. HDMI works fine.

Hope Apple can address this issue soon.

My M3 Max MBP connected to a Studio Display started flickering after updating to Tahoe. The best way to recreate is by switching from dark to light screen content. It seems like the backlight management gets confused and commands bright / dim / bright / dim a few times before resolving. It is not subtle and 100% started after the Tahoe update.

vbcbb wrote:

After updating to Mac OS Tahoe sometimes I get a slight flickering for 1-2 minutes. I use an Macbook Air M3 and I am connected to an external monitor using a Type C - Display Port cable. Before the update I didn't have any of these problems.

Did someone had this problem?

unplug all non-essential peripherals when testing.

If no issue on the internal display, I would think about the cable or Monitor as the issue and go from there

Got it! Pressing Command-backtick (⌘-`) in Brave to switch windows triggers flickering, not every time but it has happened too many times to be ignored. When flickering starts, other apps flicker as well, but not all.

Been happening since Tahoe, I notice everytime I use the Message app with dark background and switch to Finder light background or play youtube video.

It feels like low fps flickers or auto brightness auto adjust in non-smooth way.

Apple Studio Display + MacBook Pro M1 Pro in clamshell.

I have New M4 MacBook Air and yes it flickers with the built in display, especially the contacts app.

Not an external display nor cable issue.

Adding to this thread. My screen flickers for some apps. Right now only for Calendar. Flickering is around the "buttons" in the app. My thinking is that Glass is confusing the heck out of the display controller (assuming display controller means the process that 'writes' out the display). I don't have this problem with Safari.

So, tossing it out there wondering how much of this bug is about Glass.

M2 mac mini. After "upgrading" to Tahoe, one of my external 4k monitors is constantly flickering. The monitor is basically unusable.

I've tried unsuccessfully to do the following:

-Different cables from Mac Mini to monitor (USB C)

-Another power outlet for the monitor power source

-Different port on machine (USB C)

-Restarting

-Installing Stillcolor and using as directed in this discussion

-Turned off night shift

-Uninstalled any related apps for monitor control (f.lux)

Very frustrating to say the least.

If anyone has any other ideas or has gotten a solution from Apple support, please share.

I'm using an iMac 24 inch M1, 2021 with 16gm memory updated to Tahoe 26.0.1.

Since then the screen flickers terribly particularly when entering an internet search. It's very interesting and causing discomfort when using the screen. The device is also running hot.

Prior to the update it did not flicker at all - ever. And was cooler to the touch.