Just to say I am experiencing exactly the same phenomenon - and only in Firestorm. My Mac is a 2021 M1Max MacBook Pro with 32gb of memory. The flickering only began to happen recently and I have not upped my settings at all. Also, I am not experiencing it on my elderly Intel Mac mini desktop, which is about to be replaced by an M2 Mac Studio with M2 Ultra – 24‑core CPU, 76‑core GPU, 32‑core Neural Engine and 128gb of unified memory. If that flickers, it might not just be about settings but some kind of Apple Silicon compatibility issue?