Can I set the refresh or frame rate using terminal?

There isn’t a way in macOS Sequoia (or even Tahoe betas) to clamp app frame rates through Terminal, macOS doesn’t expose that level of control. System Settings > Displays only lets you pick from the refresh rates your monitor supports, and that bottoms out at 24Hz.

What you can do is lean on Accessibility settings: under System Settings > Accessibility > Display, toggling Reduce Motion and Increase Contrast tones down a lot of the heavy animations system-wide, including in Maps and App Store.

If 24Hz still feels too smooth, you’d need a third-party workaround, but I’m not aware of anything in the App Store or MacPorts that safely enforces an arbitrary fps cap per-app.

Charles Belov wrote:

Some apps have too much motion for me, an accessibility issue, and I'd like to set a lower frame rate, similar to what I can do with Firefox's layout.frame_rate setting.

Specifically, when running certain apps like App Store or Maps,

I'd like to set a frame rate of 3 frames per second to remove the smooth animation. When not running such apps, I'd switch back to the normal frame rate.

How to contact Apple for accessibility support

https://support.apple.com/en-us/HT209585

Charles Belov wrote:

So, my updated request would be, is there a third-party program which does one of the following:

—Lets me temporarily change the frame rate to an arbitrarily low level

—Lets me access the App Store through Firefox, which does let me set the frame rate to an arbitrarily low level

Good computing Charles Belov !

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