essais :

sudo nano /etc/default/grub

find the line

#GRUB_GFXMODE=640x480

edit 640x480 to your resolution eg: 1920x1080，并remove the #

for example:

GRUB_GFXMODE=1920x1080

Update by the command

sudo update-grub
là : zut !
from : https://askubuntu.com/questions/441040/failed-to-get-size-of-gamma-for-output-default-when-trying-to-add-new-screen-res#441075



grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg
https://unix.stackexchange.com/questions/152222/equivalent-of-update-grub-for-rhel-fedora-centos-systems

lspci -v
00:00.0 Host bridge: Intel Corporation 4th Gen Core Processor DRAM Controller (rev 06)
	Subsystem: Lenovo Device 3098
	Flags: bus master, fast devsel, latency 0
	Capabilities: [e0] Vendor Specific Information: Len=0c <?>
	Kernel driver in use: hsw_uncore

00:02.0 VGA compatible controller: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller (rev 06) (prog-if 00 [VGA controller])
	Subsystem: Lenovo Device 3098
	Flags: bus master, fast devsel, latency 0, IRQ 11
	Memory at f7800000 (64-bit, non-prefetchable) [size=4M]
	Memory at e0000000 (64-bit, prefetchable) [size=256M]
	I/O ports at f000 [size=64]
	Expansion ROM at 000c0000 [virtual] [disabled] [size=128K]
	Capabilities: [90] MSI: Enable- Count=1/1 Maskable- 64bit-
	Capabilities: [d0] Power Management version 2
	Capabilities: [a4] PCI Advanced Features
	Kernel modules: i915
___ (partim)

journalctl -e _COMM=gdm-x-session     #partim !
~
~
~
~
~
-- Logs begin at Thu 2020-07-23 00:08:26 CEST, end at Sun 2020-09-27 19:13:14 CEST. --
-- No entries --

inxi -Fx
System:    Host: linux.fritz.box Kernel: 5.8.4-200.fc32.x86_64 x86_64 bits: 64 compiler: gcc v: 2.34-4.fc32)
           Desktop: GNOME 3.36.6 Distro: Fedora release 32 (Thirty Two)
Machine:   Type: Desktop System: LENOVO product: 10AW008PMB v: ThinkCentre E73 serial: PC03HAUC
           Mobo: LENOVO model: N/A v: SDK0E50510 WIN serial: INVALID BIOS: LENOVO v: FCKT65AUS date: 01/12/2015
CPU:       Info: Quad Core model: Intel Core i5-4460S bits: 64 type: MCP arch: Haswell rev: 3 L2 cache: 6144 KiB
           flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 bogomips: 23146
           Speed: 898 MHz min/max: 800/3400 MHz Core speeds (MHz): 1: 963 2: 980 3: 941 4: 952
Graphics:  Device-1: Intel Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics vendor: Lenovo driver: N/A
           bus ID: 00:02.0
           Display: x11 server: Fedora Project X.org 1.20.8 driver: vesa unloaded: fbdev,modesetting resolution: 1920x1080

           OpenGL: renderer: llvmpipe (LLVM 10.0.1 256 bits) v: 3.3 Mesa 20.1.8 direct render: Yes
--- partim ---

           echo $WAYLAND_DISPLAY
=== nothing ! ===

[root@linux fds]# loginctl session-status|grep Service:
	 Service: gdm-password; type x11; class user

env|grep -E '^(XDG_SESSION_TYPE|WAYLAND_DISPLAY|DISPLAY)'
XDG_SESSION_TYPE=x11
DISPLAY=:1

gnome-shell --version
GNOME Shell 3.36.6


echo $GDMSESSION
gnome-classic


echo $DESKTOP_SESSION
gnome-classic