Screen off when running through xinit in another display?

Question

linux

I do this thing:
xinit -- :2
In theory, on a tty, which, by Ctrl+Alt+F8, should start an empty X-session with a black screen and a cursor.
In fact, X starts, mouse input works (I checked it by launching the game with xinit, there is sound, keyboard shortcuts work), but the monitor does not show a picture, the screen just turns off and goes out when you press Ctrl + Alt + F8, but does not turn back on. When I come back it's opened by Ctrl+Alt+F7 - turns on and shows my main session.
The essence of the question - how to force the image to be displayed on the monitor?

Answer 1

I tried to disable the window manager, and manually start the session.
Didn't start. Or rather, the screen is off again.
This gave me the idea that in the process of starting lightdm, something like that happens, after which the screen turns on.
I found the solution by digging into the lightdm settings. It turns out that the nvidia driver (I have a laptop with hybrid graphics) added to the scripts that start when the window manager starts up a reference to its script, which is responsible for choosing xrandr output'a. I took the xrun script
from the Arch Wiki , added /sbin/prime-offload to it, and now I can run anything in a different display using xrun <command>.

Answer 2

What about in .xinitrc?