Use defer instead of nice (it got deprecated)

main.zsh

@@ -28,7 +28,7 @@ source ~/.config/zshuper/plugins.zsh
 
 # And include highlighting at the end
 # https://github.com/zsh-users/zsh-syntax-highlighting#faq
-zplug "zsh-users/zsh-syntax-highlighting", nice:10
+zplug "zsh-users/zsh-syntax-highlighting", defer:2
 
 
 # Install and load plugins