Display Issue - Horizontal blue lines in application windows

I was having the same issue. I found a post on Google Support which worked for me.

I went into Chrome settings and toggled off the "Use hardware acceleration when available" option. Then hit the "relaunch" button next to the hardware acceleration toggle and the problem was fixed - no blue tint anymore.

ra1fee wrote:

I fixed the issue by;

1) Type chrome://flags in URL bar

2) Locate the following entry "Metal"

3) Make sure it is set to "Enable"

4) Restart browser.

Thanks, @ra1fee!

Your steps…

"chrome://flags" → "Metal" → "Enabled" → (restart browser)

…solved the issue for me.

Cheers!

🤓👍

You don't know the half of it. With Chrome, Edge, and others (Teams, etc.) you can work around it by disabling Acceleration, or for the case of Chrome and Edge - set to use Metal instead. What is really annoying to me is there are some apps that just cannot be set to not be accelerated - I am a heavy user of Unity and UE4 game engines, and both exhibit this same darn problem during level development, but in a more corrupt fashion.

This only occurs on the 16" macbooks. I have now switched to my backup 2018 macbook (15" but top specs), and it does not exhibit any issues with exact same external peripherals.

Hi GambsGonner,

I had the same problem with my MacBook Pro 16 with Catalina, and I still have the same issue with BigSur.

Following my configuration:

Anyway, I just solved enabling/disabling and re-enabling the "Automatic graphics switching" again, as shown below.

I hope this might help (hoping Apple is taking care of the issue as well ☺️)

You shouldn't reset NVRAM/PRAM unless you need to. This issue exists because of a problem with MBP and MacOS internals. There is a beta upcoming from Apple that purports to fix this as it exists mostly with hardware/GPU accelerated software displays. Resetting NVRAM will be a temporary fix and could lead to your calibration settings being incorrectly set. The best method to mitigate this is to turn off any hardware acceleration if your application has a setting for that (sometimes it is a command line argument). For example in Chrome, where this problem also exists for newer MBP, you can disable hardware acceleration or rasterization computation.

I fixed the issue by;

1) Type chrome://flags in URL bar

2) Locate the following entry "Metal"

3) Make sure it is set to "Enable"

4) Restart browser.

o, so here is what i found out. The problem is solved when you disable hardware acceleration in the settings of all the apps with this issue. like chrome, safari, Franz, and all other having the option to disable hardware acceleration. Not desired, since videos lag or just not perform as you might expect from a 2600 euro laptop.

This issue is thus related to the video card in the system or the drivers, will call apple support for a solution.

Just an update: I had the blue lines every time I connected an external monitor.

Ever since I reset the PRAM and upgraded to 10.15.5, my MacBook pro 16" runs smoothly and I no longer get the blue lines.

Reset PRAM:  pressing and holding the Command, Option, P, and R keys right as you turn the computer on.

Try to disable "hardware acceleration"

Chrome -> Settings -> Advanced -> System -> Use hardware acceleration when available -> Off

This helped me

from https://macreports.com/google-chrome-showing-blue-horizontal-lines-fix/

Yup hardware acceleration is the issue. Had this on Firefox with the lucid chart plugin of confluence. Deselected performance settings and hw acceleration and it is fixed. Issue began with a Catalina security update.

So I’ve also had this issue quite frequently lately. I noticed today that it only seems to happen when the battery is drained. If I am watching Twitch on 1 monitor and working on another the monitor pass through charging isn’t enough juice apparently. If I’m not paying attention the battery can drop to like 5-10%. The kernal_task will skyrocket, computer slows down, and then this issue happens. Not sure if this is the only cause but figured I would post it. I plugged my actual charger in today and didn’t have the issue again. Will update if it doesn’t seem to resolve moving forward.

I tried to find Metal in the flags but it wasn't there.

I did, however, discover that if I went to (three dots)/More Tools/Task Manager in Chrome, and then sorted the tasks there by name, force-quit Renderer, Spare renderer, and GPU Process, the page refreshes, the corruption cleared up and stayed cleared. It's been about 30mins and it's still clear, but I'll report back if it fails again.

Here is what i did to fix the issue in Google Chrome on my MacookPro (BigSur):

1) Type chrome://flags in URL bar

2) Locate the entry "Hardware-accelerated video decode"

3) Make sure it is set to "Disable"

4) Locate the entry "Hardware-accelerated video encode"

5) Make sure it is set to "Disable"

6) Restart browser.

cambsGooner wrote:

As you can see from the image below I have blue horizontal lines appearing within my Chrome application window

2019 Macbook Pro 16

https://discussions.apple.com/content/attachment/8a8d52eb-2aef-487c-90b7-53ddf997baac

The application is the latest build of Chrome Version 80.0.3987.163 (Official Build) (64-bit)

It has happened 3 times now - each time appear to be after the laptop has been left running overnight.

Not it is not the full display affected only the application window. I've also only seen this in the chrome browser (I've also posted this to the Chrome support site) it sometimes goes away simply by killing Chrome but this time required a reboot.

Anyone seen this before - got any ideas??

https://discussions.apple.com/content/attachment/ab77ce96-f73e-4e12-a741-ff66ffd7525c

Try resetting NVRAM/PRAM http://support.apple.com/kb/ht1379

did a new NVRAM reset calling with support. It took longer now to restart, aparently it is important the keys are pressed immediately after restart and be held untill after you see the apple logo. Some fan noise the first minute which is now ok and overall it seems fixed. Will update here if the problem is not fixed, no news is good news.