Hopefully fixing commit b9510bcaa5 as the GLPI installation doesn't work properly anymore.

Why doesn't it work: This is more of an assumption and might be something else. However, the installation worked properly with the example docker-compose.yml where no volumes were mapped, but didn't work, when the volume mapping /var/www/html/glpi/:/var/www/html/glpi was included. It could be that docker created the volume folder, the container was started, checked if the glpi directory was present (which it was) and did the additional check, if 'ls /var/www/html/glpi' did't just return 'plugins'. This check might failed since the glpi directory existed, but 'ls /var/www/html/glpi' returned an empty string and thus considered GLPI to be installed.

glpi-start.sh

@@ -22,9 +22,9 @@ then
     echo -e "TLS_REQCERT\tnever" >> /etc/ldap/ldap.conf
 fi
 
-# Check if GLPI, but not only the plugins folder is present. This way it is possible to install plugins
-# before GLPI is started which makes it easier to build custom Docker images based on diouxx/glpi.
-if [ -d "${FOLDER_WEB}${FOLDER_GLPI}" ] && [ "$(ls ${FOLDER_WEB}${FOLDER_GLPI})" != "plugins" ];
+# Check if GLPI + the index.php are installed. This way it is possible to install plugins before
+# GLPI is started which makes it easier to build custom Docker images based on diouxx/glpi.
+if [ -d "${FOLDER_WEB}${FOLDER_GLPI}" ] && [ -f "${FOLDER_WEB}${FOLDER_GLPI}index.php" ];
 then
 	echo "GLPI is already installed"
 else