Public virtual display has black screen

I ran this example: https://github.com/android/media-samples/tree/main/ScreenCapture

And changed the display to be public so that I can access it using scrcpy:

mVirtualDisplay = mMediaProjection.createVirtualDisplay("ScreenCapture",
                mSurfaceView.getWidth(), mSurfaceView.getHeight(), mScreenDensity,
                DisplayManager.VIRTUAL_DISPLAY_FLAG_PUBLIC,
                mSurface, null, null);

When I open the display using scrcpy, I get a completely black screen, while on the preview it's showing correctly.

Why is it giving a black screen through scrcpy?

I'm assuming it's because the display is not secure (the warning "WARN: Display doesn't have FLAG_SUPPORTS_PROTECTED_BUFFERS flag, mirroring can be restricted"), but there is no way for a regular app to create a secure virtual display, since the permission is for system apps only.

Any way to get it working?