Note
The instructions below concern setting up Citrix Workspace manually on Arch Linux. Alternatively, one can install Citrix through the AUR.

Download the Workspace app for Linux from the Citrix download page.

Install some prerequisite packages to ensure the GUI works properly1:

sudo pacman -Syu webkit2gtk gtk2

Assuming the Workspace app archive was downloaded to ~/Downloads, extract the archive and proceed with the installation as follows2:

mkdir ~/Downloads/Citrix
mv linuxx*.tar.gz ~/Downloads/Citrix/
cd ~/Downloads/Citrix
tar xzvf linuxx*.tar.gz
./setupwfc

Set the ICAROOT environment variable in ~/.zshrc or equivalent2:

echo '
# Citrix Workspace - ICAClient
export ICAROOT=~/ICAClient/linuxx64/' >> ~/.zshrc
source ~/.zshrc

Then, configure the certificates (this may be system-dependent)3 4:

mkdir -p $ICAROOT/keystore/cacerts/
cd $ICAROOT/keystore/cacerts/
cp /etc/ca-certificates/extracted/tls-ca-bundle.pem .
awk 'BEGIN {c=0;} /BEGIN CERT/{c++} { print > "cert." c ".pem"}' < tls-ca-bundle.pem
openssl rehash $ICAROOT/keystore/cacerts/
$ICAROOT/util/ctx_rehash

The configuration is complete and virtual desktops can now be launched by opening ICA files with Citrix Workspace Engine.

The installation files can be safely deleted at this point:

rm -r ~/Downloads/Citrix

To reinstall or uninstall the application2, run the setup script as follows:

$ICAROOT/setupwfc

Footnotes