Your iPhone boasts a stunning ProMotion display, capable of silky-smooth 120 frames per second. Yet, browsing the web often feels…less fluid. The culprit? Safari, by default, caps its rendering speed at 60fps, leaving potential performance on the table.
Fortunately, you can unlock the full potential of your display with hidden developer settings called Feature Flags. These flags allow you to tweak Safari’s behavior, pushing it beyond its standard limitations. It’s a simple change that can dramatically improve your browsing experience.
On your Mac, begin by opening Safari and navigating to the Settings. You can access these using the Command + comma keyboard shortcut, or through the Safari menu in the menu bar. Then, venture into the Advanced tab.
At the very bottom of the Advanced tab, you’ll find a crucial option: “Show features for web developers.” Click this, and a new tab labeled “Feature Flags” will appear, revealing a world of customization.
Within the Feature Flags tab, locate “Prefer Page Rendering Updates near 60fps.” You can either scroll through the alphabetical list or use the search function to find it quickly. Once found, simply deselect this option.
The change isn’t immediate. You must completely quit Safari – not just close the window – and then relaunch it for the new setting to take effect. This ensures a clean start with the updated parameters.
While most Feature Flags are intended for developers, experimenting with them is generally safe. However, it’s wise to document any changes you make. This allows you to easily revert to the original settings if something unexpected occurs.
On iPhone or iPad, the process is similar. Open the Settings app, then scroll down and tap on “Apps.” From there, select “Safari” from the list of installed applications.
Within Safari’s settings, scroll all the way to the bottom and tap “Advanced.” Finally, locate and tap “Feature Flags.” Unlike the Mac version, there’s no search function here, so you’ll need to scroll through the list.
Find “Prefer Page Rendering Updates near 60fps” and toggle it off. As with the Mac, a full restart of Safari is required. Swipe up from the bottom of the screen to access the app switcher, then swipe up on the Safari preview to close it completely before relaunching.
Remember, enabling rendering above 60fps can impact battery life. The extent of the drain depends on your usage patterns and the websites you visit. Monitor your battery performance closely.
If you notice a significant reduction in battery life after making this change, simply re-enable the “Prefer Page Rendering Updates near 60fps” flag and restart Safari. It’s a trade-off between visual smoothness and power consumption.
