Samsung's April security patch for the Galaxy S20 Ultra appears to have introduced a distinctive visual bug to the company's newest Android flagship. Several users are reporting their smartphones developed a tendency to display a distracting green overlay following the latest update.
The issue ostensibly only happens at refresh rates higher than 60Hz, both the 120Hz and the secret 96Hz refresh rate. The bulk of the complaints about this issue seem to be from Galaxy S20 Ultra owners who have the Exynos variant.
Green tint troubling only Exynos variants of the Galaxy S20 Ultra
According to numerous user testimonies, switching the Galaxy S20 Ultra to a high refresh rate and lowering its brightness to below 30% causes the problem to manifest in a wide array of apps. Samsung Pay, Camera, Calculator, Snapchat, Telegram, PUBG: Mobile, and Chrome are among the apps exhibiting the issue. A device reset reportedly solves the problem which did not exist prior to the April update. Those two facts are heavy indicators of the phenomenon being a software bug and not a side effect of some underlying hardware flaw.
We also find that this green tint appears when the phone temperature goes above 40C or the battery is at 5%, the threshold at which the refresh rate is automatically knocked back to 60Hz from 120Hz. We were also able to reproduce this issue on a device that had 60% battery and was nowhere near the temperature threshold. Basically, this tint will appear when the brightness is low and the display goes down to 60Hz inside an app. As many of you will be well aware by now, the 120Hz refresh rate doesn't work inside a lot of apps right now, most notably the Camera app. Just turn up the brightness a little bit and the tint disappears.
With that said, only owners of the Exynos 990 variant of the Galaxy S20 Ultra have chimed in to complain about the green screen issue so far. Samsung's service reps have yet to acknowledge the bug as a known issue and are still only offering case-by-case advice which largely comes down to telling users to reset their devices and clean the caches of apps wherein the green tint appears. That's just standard troubleshooting advice and doesn't do much to address this issue.
It remains to be seen whether the newly discovered problem is a limited visual artifact or a more widespread bug akin to the notorious red tint plaguing many a Galaxy S8 three years ago. Have you experienced something similar on a Snapdragon-powered variant? Share your experience with us in the comments below.
