Issue with different color picker values

So I just noticed this and I’m wondering why it’s happening.

I’ve got a swatch using a color style called “Green 1”. The hex value is 219653.
When I use an OS-level color picker utility and I hover over the same swatch, it gives me a different value.

I tried three different color picker utilities and they all agree with each other. Figma’s color picker says different, even when I selected HEX as the color format.

What’s going on here, and how do I sync these values up? What’s the “correct” value?