Different resolution on multiple screens

Hello,
I’ve got two canvases in a scene.
A camera looks at each of the two canvases.
In the code I have activated a second display.
I want one canvas in the compiled application to appear on the main screen and the other canvas on the second screen. The two screens have a different resolution.
In the Gameview of the Unity Editor everything works fine.

The problem now is that after compiling, the second screen takes over the resolution of the first screen and is therefore displayed incorrectly.

I compile the application with the player setting Fullscreen Windowed.
If I don’t activate the second screen in the code, I have the possibility to switch back and forth between fullscreen and windowed with alt+Enter and thus adjust the size.
If I activate the second screen in the code, I can no longer use the alt+Enter shortcut.

I tried different screen and display settings in the code and in the Unity editor but nothing led to success.

Here is the code I run on startup

void Start()
    {

        //Effects only the Main Screen
        Screen.SetResolution(2160, 3840, false); 

        if (Display.displays.Length > 1)
        {
            Display.displays[1].Activate(1920, 1080, 60); // Has no effect
        }

    }

In Unity I assigned the two canvases to the render mode Screen Space - Overlay.
I use the Unity version 2019.2.2f1.

I’ve been looking for a solution for two days and seemingly just can’t find one. If someone could give me a hint, that would be great.

If this ist the wrong group for this topic can anyone give my an advice where to post ist correctly?

Did you find an answer to this?

No, not an answer but a workaround.
I use two different applikations and the Spout-Plugin (GitHub - keijiro/KlakSpout: Spout plugin for Unity).
One applikation is the sender of a videostream und the other applikation is the receiver.

As far as I found out, unity doesn’t let it run to two screens with two different resolutions.
But maybe I’m wrong.
Do you have another solution for the problem?

Have you found a solution to this atleast by now?