diff --git a/scripts/actions/internal_users b/scripts/actions/internal_users
index 271987b..9e24ab7 100644
--- a/scripts/actions/internal_users
+++ b/scripts/actions/internal_users
@@ -92,28 +92,82 @@ ynh_backup_if_checksum_is_different "$final_path/conf/local.protected.php"
 # Always overwrite local file with the one from package.
 cp conf/local.protected.php $final_path/conf
 
-if [ $is_internal_users -eq 1 ];
-then
-        auth_backend="authchained"
 
-        #authchained_configuration='$conf['p	lugin']['authchained']['authtypes'] = 'authldap:authplain';'
-        #grep -q -F '$conf['plugin']['authchained']['authtypes'] = 'authldap:authplain';' "$final_path/conf/local.protected.php" || echo 'include "/configs/projectname.conf"' >> foo.bar
+if [ $is_internal_users -eq 1 ]; then
+    auth_backend="authchained"
 
-        # Search if configuration in "config file" is present for plugin to work
-        #TODO could be added straight to 'local.protected.php' file ?
-        grep -q -F '$conf['plugin']['authchained']['authtypes'] = 'authldap:authplain';' "$final_path/conf/local.protected.php"
-        if [ $? -ne 0 ]; then
-                # If not found, add the setting to "local.protected.php" which can only be edited by Yunohost
-                # \$conf needs the "\" to espace the dollar and avoid echo to interprate it as a (void) variable
-                echo "\$conf['plugin']['authchained']['authtypes'] = 'authldap:authplain';" >> "$final_path/conf/local.protected.php"
-        fi
-        # source: https://stackoverflow.com/questions/3557037/appending-a-line-to-a-file-only-if-it-does-not-already-exist
+    # Automatically install "authchained" plugin
+    # Allows to use multiple users backend storage : LDAP + internal DokuWiki users
+    # See https://www.dokuwiki.org/plugin:authchained?s[]=chained
+
+    plugin_archive=dokuwiki-plugin-authchained.tar.gz
+    wget -nv --quiet 'https://github.com/rztuc/dokuwiki-plugin-authchained/archive/master.tar.gz' -O "$plugin_archive" -o /dev/null || true
+
+    # if "file is not zero size"
+    if [ -s "$plugin_archive" ]; then
+
+        tmpdir="$(ynh_smart_mktemp --min_size=1)"   # Create a 1mb temporary folder
+        tar xzf "$plugin_archive" -C "$tmpdir"      # Extract plugin to the temp folder
+
+        # Extract the "base" field from the plugin archive to create plugin folder name
+        # See https://www.dokuwiki.org/devel:plugin_info
+        #
+        # 'wildcard' is used to avoid having to find the name of the subfolder
+        # It should not change later but who knows...
+        plugin_folder_name=$(cat $tmpdir/*/plugin.info.txt | grep url | awk -F ':' '{print $3}')
+
+        # Define the path where plugin has to be installed
+        plugin_finalpath="$final_path/lib/plugins/$plugin_folder_name"
+        mkdir -p $plugin_finalpath
+        
+        # Copy plugin files to DokuWiki plugin directory
+        # Doesn't work with "mv" so "cp" instead (taken from "upgrade" script)
+        cp -a $tmpdir/*/. "$plugin_finalpath/"
+        
+        # Cleaning
+        ynh_secure_remove --file="$tmpdir"
+
+        # Set filesystem rights for new plugin
+        chown -R $app:root $plugin_finalpath
+    fi
 else
-        auth_backend="authldap"
+    auth_backend="authldap"
+    # TODO: Disable/remove "authchained"
+
+
+    ##$plugins['authchained'] = 0;    in   plugins.local.php
+    #
+    #
+    ## Use a "sub process" to start a new shell to run these commands
+	## Allow to use only one "cd" and to be more efficent
+	#(
+    #    cd $final_path/conf
+    #
+    #    cp plugins.local.php plugins.local.php.bak
+    #
+    #    # Search if configuration in "config file" is present for plugin to work
+    #    ## -F, --fixed-strings
+    #    ##   Interpret  PATTERN  as a list of fixed strings (instead of regular expressions), separated by newlines, any of which is to
+    #    ##   be matched.
+    #    ## -q, --quiet, --silent
+    #    ##   Quiet; do not write anything to standard output.  Exit immediately with zero status if any match  is  found,  even  if  an
+    #    ##   error was detected.  Also see the -s or --no-messages option.
+    #    grep --quiet --fixed-strings '$plugins['authchained'] = 0;' "plugins.local.php"
+    #    if [ $? -ne 0 ]; then
+    #            echo "not found in file"
+    #            # If not found, add the setting to "local.protected.php" which can only be edited by Yunohost
+    #            # "\$conf" needs the "\" to espace the dollar and avoid echo to interprate it as a (void) variable
+    #            #echo "\$conf['plugin']['authchained']['authtypes'] = 'authldap:authplain';" >> "$final_path/conf/local.protected.php"
+    #    else
+    #        echo "not found in file"
+    #    fi
+    #    # source: https://stackoverflow.com/questions/3557037/appending-a-line-to-a-file-only-if-it-does-not-already-exist
+    #
+    #)
 fi
 
+
 # Set the authentification backend
-#ynh_replace_string "^$conf['authtype'].*" "$conf['authtype'] = '$auth_backend';" "$final_path/conf/local.protected.php"
 ynh_replace_string "__YNH_AUTH_BACKEND__" "$auth_backend" "$final_path/conf/local.protected.php"
 # Set the "admin" user
 ynh_replace_string "__YNH_ADMIN_USER__"   "$admin"        "$final_path/conf/local.protected.php"
diff --git a/scripts/install b/scripts/install
index 8297dcb..855a041 100755
--- a/scripts/install
+++ b/scripts/install
@@ -71,7 +71,8 @@ ynh_app_setting_set $app language $language
 # Can be changed by action script "internal_users"
 auth_backend='authldap'   # Default backend is LDAP with Yunohost, 'authldap' for DokuWiki
 ynh_app_setting_set $app auth_backend $auth_backend
-# Disable the 'is_internal_users' feature
+
+# Force disable the 'is_internal_users' feature
 ynh_app_setting_set $app is_internal_users 0
 
 #=================================================