Might be a known issue already fixed in Chrome Canary which you can install separately.

I tried to reproduce this using Chrome 68.0.3440.106 on two MacBook Pros running 10.12.6 and 10.13.6, respectively, but was not able to see any green artifacts (I had the RGB Color Picker set to the exact values in the image above).

It might be more hardware-specific.  Could you let us know what type of Mac are you seeing this on?

I’m using the 2.8 GHz variant of a MacBookPro11,3 running 10.12.6 

Also, I just discovered that it is only doing this on my external monitor, NOT on the built-in retina screen. Sorry, I should have checked that earlier.

Unable to reproduce the issue on reported chrome version 68.0.3440.106 using Mac 10.12.6. Attaching screen-cast for reference.
Steps: 
---------
1. Launched reported chrome 
2. Enabled external monitor setup
3. Navigated the URL " https://www.google.com/search?q=rgb+color+picker&oq=rgb+color&aqs=chrome.0.0j69i57j0l4.1997j1j7&sourceid=chrome&ie=UTF-8 "
As we are not seen green color as per screen-cast 

@Reporter: Could you please review the attached screen-cast and confirm if anything being missed here. Request you to retry this issue with fresh profile without any extensions/apps or reset all the flags and let us know if issue still persists.

NOTE: Observed the issue with and without External monitor setup 

Thanks.!

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	874184.mp4 2.2 MB View Download

I watched your screencast. The only comment I have is that the issue is most prevalent in the magenta band, with the blue and red also having the issue, but it stops before you get to cyan.

I’m seeing it on an Eizo CG241W monitor calibrated for prepress color work. I just now did a recalibration with ColorNavigator using an X-rite I1 Display for measurement, and am still seeing the issue, BUT if I switch to an uncalibrated sRGB profile the issue goes away. Interesting.

Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Unable to reproduce the issue from our end on reported chrome version 68.0.3440.106 using Mac 10.12.6, 10.13.3 (With retina) and 10.13.6. As per comment #5 issue related to Eizo CG241W monitor calibrated. Hence adding "TE-Hardware-Dependency" label to it and requesting respective team to have a look in to it for further inputs on it. 

Thanks..!

I found this report while looking for similar issues - I'm seeing red blocks in dark sections of images.  Other browsers have no issues.
I'm also on a calibrated Eizo external monitor - an Eizo CS240.  

Turning off hardware acceleration fixes it but that has other side effects like Chrome behaving like it isn't color aware (colors are all wrong, very saturated)

Deleted: chrome-scrn-shot.jpg 80.7 KB

	chrome-scrn-shot.jpg 80.7 KB View Download

Tested with an Apple Thunderbolt monitor today, and the issue did not occur. Problem might be specific to Eizo monitors.

I forgot to mention that I'm on Windows 10, Dell Precision 5520 laptop.