mate-session auto suspend if & is being used

[JanuszChmiel]

I have tried to start desktop environments in Arch Linux ARM64 by using The following approach

unset SESSION_MANAGER
unset DBUS_SESSION_BUS_ADDRESS
export LD_PRELOAD=usr/lib/libandroid-shmem.so

export DISPLay=:0
Then I have install xinit package and X86 video dummi driver
I have installed x11-vnc
I had to use special xorg.conf file
then I have started xinit &
I have started x11vnc by typing

x11vnc -display :0 -bg -nopw -listen localhost -xkb -forever -ncache 10 -ncache_cr -noshm

I have not used -noshm because x11vnc allocates too many shared memory regions so it crashes even while using yours library.
The advantage of my approach is that GUI of X11 apps will never crash because of The need to switch between Termux window and X11vnc screen.
I Am using TCP/IP sockets to communicate with Pulseaudio sound server which run from Termux.
I Am using dummy video driver because screen output is not important for Me. I do not see at all. And XVFB or other VNC apps produces graphical output which produces crashes while using Firefox or other apps which require OPENGL or 3D hardware acceleration.
but when running mate-session &
it allocates some shared memory regions but it automatically suspend. But when I do not use mate-session with & char, it do not crash. It do not suspend mate-session.