if installing eos i3 aside with a full DE you need to remove dex from running automatic… it will start parts from the DE what can cause issues…
# dex execute .desktop files
# keep in mind that it can cause issues
# when second to i3 a DE is installed or mixed usage of i3 + xfce4 or GNOME
# in this cases better disable dex and use manual starting apps using xdg/autostart
exec --no-startup-id dex -a -s /etc/xdg/autostart/:~/.config/autostart/