Display Issue - Horizontal blue lines in application windows

Zapping the NVRam gets me working again, but only temporarily, and that's with the new logic board. Changing the logic board did not resolve the issue in my case. What did jinx me was posting above that it miraculously fixed itself after a while. A day after I posted that, the glitching returned just to rub my nose in it.

What I did find was that it seemed to have something to do with switching between battery operation and AC adaptor operation, and potentially with going from one display set up, say, like at home with my 27" and 24" monitors, and my office configuration, which is a 20" 1920x1080 monitor. I can pretty much guarantee that it will happen once I get back to my main configuration in my home office with the two monitors. However, if I do the reset, I can work with that configuration for weeks and not see the problem occurring.

I have automatic graphics switching disabled on the advice of another person with this problem who reported it lowered the occurrence of the problem.

If it is an internal hardware issue, out of warranty it will be a challenge. I just had my 2020 MPB 16 repaired. It was a faulty internal display ribbon connecting the display to the logic board. Display had to be replaced because the cable is attached to the display screen. If you want assistance, you must work with the apple store, in hope of getting any financial assistance. Apple Care senior level support is of little assistance. I was not successful. Paid out of pocket because I mistakenly agreed to pay for the out of warranty work at the apple store, locally. You would need to protest the problem in the Apple store to get any assistance, if possible. There should be lemon laws for high end consumer hardware. I filed a complaint with apple/feedback per online apple care case worker phone service. Their quality of support is great. But their coverage of design flaws could be better.

Yes, the second time doing the NVRAM reset it took longer to start, that makes me think the first time it was not done correctly. So far no blue lines anymore.

Try resetting PRAM and updating the OS first. That worked for me.

I can definitely confirm that macOS 11 Big Sur has definitely resolved the issues. I do hope they backport these fixes to Catalina for those who do not want to use the new beta.

Definitely an issue with hardware acceleration. Disabled on browser and fixed for now.

It seems like that the common denominator for this problem is Mac 2019 16 inch and the latest update. I have the same issue when using chrome and only certain apps (WhatsApp etc). Disabling Hardware acceleration helps but it's not a solution as many websites will start running sluggishly without it.

If I was to guess I think the latest update introduced some changes to the graphic card driver that don't work well with Chrome.

I had a lot of issues with 10.15.4. The distorted screen, crashes during sleep when docked, external monitor not detected after sleep. I'm using 10.15.5 for 1 1/2 days now and all of this seems fixed (I restored energy saving settings to defaults).

The macOS 11 Big Sur Beta (1 and 2) have been a success. The issue is completely resolved, and in fact all my main issues are resolved (though one new one - no audio over my external display).

Finally.. a macOS release that works since the first developer preview, where as Catalina is still haunted with issues to this day.

This appears to be a chromium issue - any app that is written on the back of chromium has this issue - goggle chrome browser, brave browser, Notion.so.

it will temporarily reset when the machine is rebooted and I have found only occurs after the machine has been left on for a couple of days and therefore has been in and out of sleep mode.

It seems all we can do is await macOS 11 Big Sur!!

I agree with Tallmacdude. This issue appears in Microsoft Teams and 1Password as well. For Mircrosoft Teams I read somewhere that disabling the GPU Hardware acceleration within the general settings section of teams would fix the problem, however forget about using teams for video calls or screen-share. It's near impossible to view the screen as the video feed is so choppy and bad.

Added Firefox to the list.

It's just a theory right now, but here's the following account of how my glitches occur:

1. Typically, the glitches trigger especially after the mbp wakes from sleep after a longish period (a few hours to overnight – this has been experienced rather consistently since April)
2. The likelihood of the glitch triggering is much higher if I have webGL / HW-accelerated graphic views actively rendered when the mbp goes to sleep
3. After the glitch triggers, any application that attempts to access hardware-accelerated graphics in a particular way/routine will result in the glitch in the application as well – in this case, Chromium being one candidate, but now we know that Safari and Firefox do the same too. For example, I could wake the mbp in the morning, get the glitch in Safari, and have this same glitch show up by opening any software in the list below
4. This problem is not necessarily tied directly to Chromium anymore. Could this be a deeper hardware fault?

Current list of software known to have the blue glitches (when it triggers, see above):

1. Safari Version 14.0 (15610.1.28.1.9, 15610) (specifically, WebGL content)
2. Firefox 82.0.2 (64-bit) (specifically, WebGL content)
3. Google Chrome 86.0.4240.111 (Official Build) (x86_64) (specifically, WebGL content)
4. Miro 0.4.2 – main window doesn't glitch, but Developer Tools does
5. Spotify 1.1.45.621.gdddebadc – main window doesn't glitch, but speaker selection popup does

As I mentioned in my previous comments, interestingly, the two applications listed below seem to not have the glitches anymore – perhaps via a recent update from the developers? Did they figure out a way to work around the hardware acceleration glitch, or simply chose not to rely on h/w acceleration for some of the views causing the problem?

1. Adobe Lightroom Classic 9.3 Build [202005281810-476e492c]
2. Microsoft Teams 1.3.00.28778

It's now been over 24 hours with no reappearance of the glitching in Chrome. Note, I did not restart, zap the NVRAM or PRAM, I just did the force-quitting of Renderer, Spare renderer, and GPU Process in the Chrome app Task Manager. I will keep reporting my observations.

See https://apple.stackexchange.com/a/414669/12345 for several workarounds.

If you don't want to restart your browser, try running the following from Terminal.app.

killall "Google Chrome Helper (GPU)"

So, I thought it might be interesting to note that if I turn on my computer from being completely shut-down, at home, running a Thunderbolt 3 to MDP to DP chain of adaptors to a 27" Dell display, and to a USBC to USB3-HDMI-Ethernet dongle connected to another 24" Dell display, and keeping the laptop open (2019 MBP running Big Sur), the glitch will not appear. I can operate for days and not see it.

However, if I unmount my external drives, disconnect the dongles, and go mobile, using the laptop on battery, then go back home and reconnect to the dongles and try to work again from home, it happens 100% of the time. Fully reproducible. I need to then restart to get Chrome, Safari, WhatsApp to work without the graphics glitching again.

I have disabled the "Automatic graphics switching" and the behaviour continues.

My mainboard has been replaced. I have re-installed from a USB drive, from a web install, new account, no old setting, no old account corruption, and this happens.

It's not my mainboard, it's not a program I'm running that is exhibiting this behaviour on other computers, it's not my account, it's not my OS installation, it is clearly, undeniably, a fault with this model of computer that Apple seems to be unprepared to admit, should they be forced to recall them and replace them with an equivalent feature set laptop that doesn't do this.

[Edited by Moderator]