I've been experiencing also screen discoloration on my note 9 for months but I've found a simple solution. No need to install third party app for temporary fix as it may damage the screen permanently. All you need to do is ACTIVATE your "ALWAYS ON DISPLAY" and set to always ON.
Ensure that "always on display" already appeared on the screen(with slight delay) before turning on your screen. That's it! Hope this helps but it's just still temporary.
To SAMSUNG, hope you can find ways to permanently fix this.
It worked for a few months and then eventually the problem came back. What a nuisance! Its a software issue and Samsung themselves are at fault. They f'ed up the display via updates and now refuses to patch it (since the support ended)
If you screen is yellow and screen is not visible clearly and discoloration, brightness bar adjustment is a problem, and unable to view or see the screen with high resolution,
Many people feel it's a display problem and then they replace the display,
But it's 100% not a display problem, it's software issue on samsung galaxy note 9 device.
Solution: Please use OLED Saver app from Google,
Once download - Install- Enable OLED Saver
Then please observe the difference on display, before and after.
And we can able to watch HDR videos on youtube on SAMOLED resolution after installing OLED Saver app.
Please try, it will not cause any issue on the mobile, i am using from last 1 year. If not satisfied you can uninstall the app.
