Pink Boot Screen after Catalina upgrade.

I fixed my full time pink screen issue, here is the solution.

The reason it is having an issue, is after the update, the signal being sent is YCbCr instead of RGB like your monitors are expecting. Some people with panels like mine will get pink, others likely get no signal recognized. This script works by setting up a profile for your specific monitor, and having it be forced to be RGB, if you connect it to another model monitor with the same issue, this process will need to be repeated for that monitor as well.

1. Download this script: https://gist.github.com/adaugherity/7435890
2. Place the patch-edid.rb file into the /Users/ directory
3. Run this command in Terminal: ruby /Users/patch-edid.rb
4. Take note of the DisplayProductID and DisplayVendorID file names. These will vary based on your monitor.
5. Move the output file named "DisplayProductID-XXXX" from /Users/~username/ to the /Users/ directory
6. Reboot your Mac in Recovery Mode by pressing Command+R as soon as you see the Apple logo after rebooting
7. Open Disk Utility in Recover Mode
8. Check to see if "Macintosh HD" is mounted. If it isn't you will need to mount it before proceeding.
9. Exit Disk Utility
10. Open Terminal in Recovery Mode
11. Change to the Overrides directory via "cd /Volumes/Macintosh\ HD/System/Library/Displays/Contents/Resources/Overrides/"
12. Create the folder with "mkdir DisplayVendorID-XXXX".
13. Run this command in Terminal (make sure to include spaces):
14. "cp /Volumes/Macintosh\ HD/Users/DisplayProductID-XXXX /Volumes/Macintosh\ HD/System/Library/Displays/Contents/Resources/Overrides/DisplayVendorID-XXXX/"
15. Restart computer and the monitor should now be in RGB mode.
16. Check to make sure it has taken effect by going to your "system preferences" and clicking "displays". If your display name at the top bar does not include "forced RGB mode (EDID override)", it did not take effect.

Hope this helps everyone! if you have issues look in the comments on the script page, the author is active.

My machine is a Mac mini (2018) i7 64GB 1TB. My monitor is a 28 inch Hannspree HF289H monitor

I had the same problem and tried the same solutions as you on my Mac Mini (under one year old).

Nothing worked, the screen was permanently pink.

See my previous post. I partitioned the hard drive and clean installed Mojave.

When I booted back to Catalina it worked perfectly and has ever since.

Use the OSD menu and set resolution to 1920 x 1080. How long is the cable? If it’s longer than 3 feet, that could also be an issue. If changing the resolution and/or shorter cable don’t work, get a new monitor. Your monitor is over 8 years old and running HDMI 1.0 = obsolete. Good luck.

This most likely means something to do with your system configuration/ apps installed. In other words, most likely not a hardware problem. When time permits, backup and factory reset. That should solve the problem for you.

Just released - Catalina 10.15.1 - try it?

What display and how is it connected to your Mac Mini?

(brand, size, cable and adapter if one is used)

Why are you shutting down instead of sleeping the Mac Mini?

(my Mac Mini's sleep 24-7 without any issues)

I had this same problem.

So, I partitioned the hard drive and clean-installed Mojave.

Mojave did not have the pink screen.

I then rebooted from the Catalina hard drive and now my monitor is functioning as it should.

Maybe someone can explain this?

Have you tried rebooting to safe mode to see if the same thing happens?

I have the same problem. It lasts a few seconds and only during startup. My monitor is a Benq BL2420PT, running at 2560 x 1440 (standard resolution), connected to HDMI port with top quality ultra high speed cable, but I'm positive it has something to do with macOS Catalina 10.15 upgrade, as this issue began the same day it was installed on my Mac Mini 2018.

Same issue here - except the pink screen continues beyond the initial login.

Clearing the NVRAM (https://support.apple.com/en-gb/HT204063) worked briefly - the login screen displayed in full colour, however once I entered my password and the desktop displayed, it reverted back to the pinkish/purple hue.

Booting in Safe Mode had no effect.

This is with a brand new Mac mini (unboxed this morning), which worked fine until the Catalina upgrade.

Switching monitors and cables (with another working High Sierra Mac mini) has no effect.

Will be downgrading next and let Catalina age on the shelf for six months...

I ended up downgrading to Mojave - colours are back, everything works fine.

As of now, it’s related to the make/model/resolution/connection type of the monitor. Unless the monitor is Mac-certified and/or you involve the monitor manufacturer meaningfully, they remain suspect. Upgrading to Catalina may only have brought latent bugs to surface, as it appears to be in your case.

I do hope the problem gets fixed but it’ll take more than forum-punching Apple (feel free to post a separate thread with details). Good luck.

Happy to hear. Maybe you should open a ticket with BenQ about their HDMI not supporting the Catalina pink-boot feature...jk :)

Thanks again hcsitas, its definitely a Catalina issue, I clean installed Mojave again and my monitor is fine. Does that mean Mojave supports my HDMI version but Catalina doesn't? Seems odd...