我最近将我的电脑从功能齐全的 18.10 系统升级到了 19.04。
Plymouthd 似乎不再加载启动画面。图形用户界面不再自动加载，在保持黑色之后，它似乎切换到详细的文本控制台，并在那里停止。如果我按下Ctrl-Alt-F2，我会得到 tty2 文本登录屏幕。
然后使用 切换回主屏幕Ctrl-Alt-F1，Gnome UI 现在加载。
问题是我需要做什么才能让 Gnome 在重启后自动进入图形登录屏幕？
更新：
sudo systemctl get-default
graphical.target
cat /etc/default/grub
# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
# info -f grub -n 'Simple configuration'
GRUB_DEFAULT=0
GRUB_TIMEOUT=0
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
#GRUB_CMDLINE_LINUX_DEFAULT="verbose"
GRUB_CMDLINE_LINUX=""
# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"
# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console
# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480
# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true
# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"
# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"