Why do I see screen tearing on distant ridgelines in FSR mode?

I felt totally immersed in the open world until I noticed jagged fluctuations on distant ridgelines, which completely ruined the artistic vibe. I first tried enabling forced anti-aliasing in the driver, but it just created weird ghosting effects that left me puzzled. To fix this, I used the GamePP Image Sampling Calibrator to set the FSR sharpening intensity to 65 and optimized the reconstruction sampling step. According to RivaTuner, the tearing vanished, sampling rates hit 90% via GamePP tool, and GPU temps stayed at 60-66℃ per AIDA64.