screen is detected in macOS Sequoia 15.2 on my iGPU but turns black after boot sequence

I think what you need to research is how to run your Hack in a 'Headless Setup'. In this mode, it utilizes the Graphics in the CPU (iGPU) that has integrated graphics and a Dedicated Graphics Card (dGPU). This can also depend on the SmBIOS (Mac Model) to enable this function. I am running my machine in this mode as shown in the attached. Both Graphical capabilities are utilized when needed. Good luck.

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