kinda minor but to fix bootsplash, replace the APPEND line in /boot/extlinux/extlinux.conf with
EDIT: See Upokup's post below before making the change.
APPEND initrd=/boot/initrd.img-${kernver} console=ttyS2,1500000 console=tty1 root=UUID=${UUID} rw rootwait video=eDP-1:1920x1080@60 video=HDMI-A-1:1920x1080@60 quiet splash plymouth.ignore-serial-consoles
careful not to add any new lines or make any typos!
EDIT: See Upokup's post below before making the change.
APPEND initrd=/boot/initrd.img-${kernver} console=ttyS2,1500000 console=tty1 root=UUID=${UUID} rw rootwait video=eDP-1:1920x1080@60 video=HDMI-A-1:1920x1080@60 quiet splash plymouth.ignore-serial-consoles
careful not to add any new lines or make any typos!