Can True Tone stay on for the built-in display but not affect my external monitor?

Hi everyone,

I use a MacBook Pro (16-inch, M3 Pro) running macOS Golden Gate 27.0.1. It’s connected to a Dell S2725QC 4K monitor over USB-C, and I keep the MacBook’s lid open.

When True Tone is on, it also changes the colour temperature of the Dell monitor. I’d like to keep True Tone on for the MacBook’s built-in screen while the Dell shows its normal colours.

What I’ve found so far:

• True Tone has only one switch, under the built-in display’s settings. There’s no separate True Tone option for the Dell.
• Turning True Tone off fixes the Dell, but then the MacBook screen loses True Tone too.
• Closing the lid also fixes it, but I want to use both screens.

Is there any way, such as a setting, Terminal command, or automation, to keep True Tone on for the built-in display only?

Thanks!