ProMotion displays on recent iPhones, iPads, and Macs support smooth 120Hz animations, but Safari defaults to 60Hz page rendering. This makes scrolling feel choppier than in Chrome or Firefox for some users. A hidden setting in Safari's Feature Flags can unlock the higher refresh rate for a more fluid experience.

The difference is most apparent when scrolling text-heavy pages, reducing perceived blur and judder. Apple likely defaults to 60Hz to conserve battery life, a trade-off many users may not want. The toggle is buried in developer menus, requiring a few extra steps on Mac but straightforward on iPhone and iPad.

Enabling 120Hz rendering on iPhone or iPad involves turning off "Prefer Page Rendering Updates near 60fps" in Safari's Advanced Feature Flags. On Mac, you must first enable "Show features for web developers" in Safari's settings. This works on any Mac with a ProMotion display, including 14-inch and 16-inch MacBook Pro models from 2021 onward.