Yes. I had actually upgraded & rebooted last night, noticed the breakage, then just reverted to a snapshot to deal with it in the morning.
What I've done to fix it now is to get the config from /etc/skel and then replace the font with my chosen font (which was the old one)
cp /etc/skel/.config/alacritty/alacritty.yml ~/.config/alacritty/alacritty.yml && sed -ri 's/FiraCode Nerd Font Mono/FantasqueSansM Nerd Font Mono/g' ~/.config/alacritty/alacritty.yml
Edit to add: FantasqueSans Nerd Font Mono is now FantasqueSansM Nerd Font Mono [emphasis added]