It only happens with "Classic Theme" by the way, when you are trying to change the color.
If you choose one theme from the gallery, everything's fine.

I modified my theme from blue to green but as you'll see in the following screenshot: The color above the address bar hasn't changed to green, but it's still blue.
While configuring in the editor it was green as intended, but after saving it changed to blue again. This seems to be a bug, as it hasn't happened before.