After last update I don't see Intel VGA anymore

Well, sorry if i don’t follow along 100% the discussion you linked on arch forums. Is your duty to trim the information.
You can place the 10-nvidia-drm-outputclass.conf as suggested in the wiki or as whoever mentioned it on that arch forum. Both places are valid.
You can simply create a blank file with
sudo touch /etc/X11/xorg.conf.d/10-nvidia-drm-outputclass.conf
or
sudo touch /usr/share/X11/xorg.conf.d/10-nvidia-drm-outputclass.conf
then edit it and add as per wiki the

Section "OutputClass"
    Identifier "nvidia"
    MatchDriver "nvidia-drm"
    Driver "nvidia"
    Option "AllowEmptyInitialConfiguration"
    Option "PrimaryGPU" "yes"
    ModulePath "/usr/lib/nvidia/xorg"
    ModulePath "/usr/lib/xorg/modules"
EndSection

Or do it from another file you copy and then replace the lines … is up to you, just don’t make typos in it.
Reboot and test your dual screen.

If you have issues with Screen tearing with nVidia driver, as per that wiki, then you create the other file and add those lines to it and reboot, test …

By the way, what did you do when you first installed the system? Did you took notes about that? Or there was nothing special what you did, and worked by default?

Listen, it is the first time I have heard about this configuration.
My system is up with Manjaro since more than 2 years.
It was working with two monitors since last week.
Do we need to make this configuration for G5 after the installation? I do not remember I have done, but it was more than two years back…

I’m reading … but i do get your tone.

What changed? If you just switched to the 5.19.1 kernel, have you also tried to boot, without touching the configurations, into another kernel? Maybe 5.15 …
Your system is a Laptop with dual GPU

Is the first time to see such system that does not make use of video-hybrid-intel-nvidia-prime driver, so after reading that wiki, to me it appeared that to be a special case and that is what it needs to be used, and based on that information, those files are a requirement.

With that said, hope you get it fixed.

I have created the file:

[dellg5 ~]# ls -ltr /etc/X11/xorg.conf.d/10-nvidia-drm-outputclass.conf
-rw-r--r-- 1 root root 257 Sep  3 18:03 /etc/X11/xorg.conf.d/10-nvidia-drm-outputclass.conf
[dellg5 ~]# cat /etc/X11/xorg.conf.d/10-nvidia-drm-outputclass.conf
Section "OutputClass"
    Identifier "nvidia"
    MatchDriver "nvidia-drm"
    Driver "nvidia"
    Option "AllowEmptyInitialConfiguration"
    Option "PrimaryGPU" "yes"
    ModulePath "/usr/lib/nvidia/xorg"
    ModulePath "/usr/lib/xorg/modules"
EndSection

and made:

  • sudo mkinitcpio -P
  • reboot

After reboot nothing changes. Same DELL logo on screen connected to HDMI and Manjaro is on the screen connected to the DisplayPort.
Any good idea?

There was a small update, few packages, not the kernel if I remember well

If I only have kernel 5.19:

[dellg5 ~]# mhwd-kernel -li 
Currently running: 5.19.1-3-MANJARO (linux519)
The following kernels are installed in your system:
   * linux519

why mkinitcpio is checking 5.17 ?

[dellg5 ~]# mkinitcpio -P
==> Building image from preset: /etc/mkinitcpio.d/linux517.preset: 'default'
  -> -k /boot/vmlinuz-5.17-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-5.17-x86_64.img
==> ERROR: '/lib/modules/5.17.15-1-MANJARO' is not a valid kernel module directory
==> Building image from preset: /etc/mkinitcpio.d/linux517.preset: 'fallback'
  -> -k /boot/vmlinuz-5.17-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-5.17-x86_64-fallback.img -S autodetect
==> ERROR: '/lib/modules/5.17.15-1-MANJARO' is not a valid kernel module directory
==> Building image from preset: /etc/mkinitcpio.d/linux519.preset: 'default'
  -> -k /boot/vmlinuz-5.19-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-5.19-x86_64.img
==> Starting build: 5.19.1-3-MANJARO
  -> Running build hook: [base]
  -> Running build hook: [udev]
  -> Running build hook: [autodetect]
  -> Running build hook: [modconf]
  -> Running build hook: [block]
==> WARNING: Possibly missing firmware for module: xhci_pci
  -> Running build hook: [keyboard]
  -> Running build hook: [keymap]
  -> Running build hook: [filesystems]
==> Generating module dependencies
==> Creating gzip-compressed initcpio image: /boot/initramfs-5.19-x86_64.img
==> Image generation successful
==> Building image from preset: /etc/mkinitcpio.d/linux519.preset: 'fallback'
  -> -k /boot/vmlinuz-5.19-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-5.19-x86_64-fallback.img -S autodetect
==> Starting build: 5.19.1-3-MANJARO
  -> Running build hook: [base]
  -> Running build hook: [udev]
  -> Running build hook: [modconf]
  -> Running build hook: [block]
==> WARNING: Possibly missing firmware for module: qed
==> WARNING: Possibly missing firmware for module: qla1280
==> WARNING: Possibly missing firmware for module: qla2xxx
==> WARNING: Possibly missing firmware for module: bfa
==> WARNING: Possibly missing firmware for module: xhci_pci
  -> Running build hook: [keyboard]
  -> Running build hook: [keymap]
  -> Running build hook: [filesystems]
==> Generating module dependencies
==> Creating gzip-compressed initcpio image: /boot/initramfs-5.19-x86_64-fallback.img
==> Image generation successful

you have probably some leftovers from the eol 5.17 kernel, so check with:

ls /etc/mkinitcpio.d/*.preset
sudo ls /boot/initramfs-*
sudo ls /boot/vmlinuz-*
sudo ls /usr/lib/modules/*

try switching to the 5.15 lts kernel and see if it helped
check if you can switch your graphics in bios
and until you installed video-linux you were running primary on your nvidia

I have just installed 5.15 and it does not help, same problem

My BIOS should be ok because I have dual boot and Windows works with two monitors

I think so…

with bios i meant, some bioses have a option to switch between gpus, and to try it out if you have it
i noticed you have som amd conf there, but you are running intel+nvidia, provide output from:
find /etc/X11/ -name "*.conf"

I haven’t found any GPUs option in the BIOS of my Dell G5.

[dellg5 ~]# find /etc/X11/ -name "*.conf"
/etc/X11/xorg.conf.d/10-optimus-manager.conf
/etc/X11/xorg.conf.d/10-nvidia-drm-outputclass.conf
/etc/X11/xorg.conf.d/00-keyboard.conf
/etc/X11/mhwd.d/nvidia.conf
[dellg5 ~]# cat /etc/X11/mhwd.d/nvidia.conf
# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig:  version 515.65.01

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0"
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
EndSection

Section "Files"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Unknown"
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
	Option "NoLogo" "1"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Extensions"
    Option         "COMPOSITE" "Enable"
EndSection

 
Section "InputClass"
    Identifier          "Keyboard Defaults"
    MatchIsKeyboard        "yes"
    Option              "XkbOptions" "terminate:ctrl_alt_bksp"
EndSection

so you have installed optimus… did you had it installed when the screens were working, or you installed it afterwards?
post output from:
pacman -Qs optimus

I have installed few months back for the problem I have with minimized application:

but it was not solving the issue.

[dellg5 ~]# pacman -Qs optimus
local/optimus-manager 1.4+r12-1
    Management utility to handle GPU switching for Optimus laptops (Git version)

so remove it:
pamac remove optimus-manager
reboot and see if it helped

You are a genious!
The problem is now solved!
Thank you very much @brahma !