Update troubleshooting section (codeenigma#192)

* Update troubleshooting section

* Remove extra space

(cherry picked from commit d812bad)

Author: matason

docs/Troubleshooting.md

@@ -8,7 +8,7 @@ The way some editors behave on save means the inumber of the file does not chang
 
 ## Cgroup Issues
 
-If your ce-dev is failing to even start the controller then you'll see a response that looks like this.
+If your ce-dev is failing to even start, or starts but then immediately exits the controller (or any container) then you might see a response that looks like this.
 
 ```bash
 Creating ce_dev_controller_2 ... done
@@ -17,6 +17,8 @@ Ensure user UID match those on the host... !
     Error: Command failed: sudo docker exec ce_dev_controller_2 /bin/sh /opt/ce-dev-ownership.sh 1000 1000
 ```
 
+Alternatively, you might not see anything at all, and you'll discover your controller (or container) isn't running.
+
 There will be very little in the way of logs or errors from this. Just an indication of a problem.
 
 ### Ubuntu 21.x
@@ -58,6 +60,11 @@ sudo update-initramfs -c -k all
 ```bash
 docker rm $(docker ps -aq)
 
+### Arch Linux
+1 - Edit `/boot/loader/entries/XXXX-XX-XX_XX-XX-XX_linux.conf` and append `SYSTEMD_CGROUP_ENABLE_LEGACY_FORCE=1 systemd.unified_cgroup_hierarchy=0` to `options`
+
+2 - Reboot
+
 ### Cgroup On Older Projects
 
 ce-dev does allow for the use of Cgroup 2, but some older projects will need upgrading to allow this to work. This means that the ce-dev controller will work fine, but some projects may fail to start some containers. This error will become apparent if you see the "unreachable" error when running the `ce-dev provision` step.