The QHD screen on the XPS 9360 is beautiful, but fonts are an issue in some cases because of HiDPI support in Linux being kinda fragmented. I had to make the grub font much larger to make grub usable.

Here’s what I did:

#prepare a font to be used by grub
$> sudo grub-mkfont --output=/boot/grub/fonts/DejaVuSansMono20.pf2 --size=20 /usr/share/fonts/TTF/DejaVuSansMono.ttf

#Edit grub's config so that it references the newly created font

$> cat /etc/default/grub | grep GRUB_FONT

#This will make grub reload its config file(s)
$> sudo update-grub

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