Emacsclient Does Not Recognise Compose Key Sequences

Originally published 2021/10/27. Updated to include the .xssessionsrc point

I run pretty often into this issue, so this is a checklist for me.
Issue being, that I cannot use Compose key sequences to type out the characters I need.

Case in point being, the apostrophe ’ and the quote marks “” , ‘’ that I use, all the live long day.

1. Make sure that emacs is running as a service. It runs in your user, so check status with systemctl --user status emacs.service
   • Do the normal computer user thing. Restart the service.systemctl --user restart emacs.service.¹
2. Make sure the system is UTF-8 everywhere. (en_IN.UTF-8 does not work for me. Make sure it’s en_US.UTF-8)
   • One place that Emacs looks is the .xsessionrc file in the home folder.
     • These are the contents of mine. My Emacs refuses to let the compose key sequences work, unless it’s present

       LC_NUMERIC=en_US.UTF-8
       LC_MONETARY=en_US.UTF-8
       LC_PAPER=en_US.UTF-8
       LC_NAME=en_US.UTF-8
       LC_ADDRESS=en_US.UTF-8
       LC_TELEPHONE=en_US.UTF-8
       LC_MEASUREMENT=en_US.UTF-8
       LC_IDENTIFICATION=en_US.UTF-8
       LC_TIME=en_US.UTF-8
       PAPERSIZE=a4
       LANGUAGE=en_US
       LANG=en_US.UTF-8
       
       if [ $DISPLAY != ":0" ]
       then
       	export XAUTHORITY=${HOME}/.Xauthority
       fi

This should do the trick 99% of the time.