diff --git a/conf/default.env b/conf/default.env
index c2115e9..e03cada 100644
--- a/conf/default.env
+++ b/conf/default.env
@@ -26,7 +26,7 @@ MAIL_USERNAME=null
 MAIL_PASSWORD=null
 MAIL_ENCRYPTION=null
 MAIL_FROM_ADDRESS='__EMAIL__'
-MAIL_FROM_NAME="__EMAIL_FIRSTNAME__ __EMAIL_LASTNAME__"
+MAIL_FROM_NAME='__EMAIL_FULLNAME__'
 
 DEMO_MODE=false
 
diff --git a/doc/POST_INSTALL.md b/doc/POST_INSTALL.md
index 46caabd..fa4a2d9 100644
--- a/doc/POST_INSTALL.md
+++ b/doc/POST_INSTALL.md
@@ -1,6 +1,6 @@
 Please open your __APP__ domain: https://__DOMAIN____PATH_URL__
 
-The username is: __EMAIL__
+The username is the administrator's email address
 The password is the administrator one you filled during the installation
 The secret is: __API_SECRET__
 
diff --git a/scripts/install b/scripts/install
index fd9eba3..4d1a9b5 100755
--- a/scripts/install
+++ b/scripts/install
@@ -10,27 +10,24 @@ source _common.sh
 source /usr/share/yunohost/helpers
 
 #=================================================
-# RETRIEVE ARGUMENTS FROM THE MANIFEST
+# GENERATE KEYS AND RETRIEVE ADMIN USER INFO
 #=================================================
 
 api_secret="$(ynh_string_random --length=32)"
 app_key="$(ynh_string_random --length=32)"
 phantomjs_key="$(ynh_string_random --length=32)"
-email_firstname="$(ynh_user_get_info --username=$admin --key=firstname)"
-email_lastname="$(ynh_user_get_info --username=$admin --key=lastname)"
+
+email_fullname="$(ynh_user_get_info --username=$admin --key=fullname)"
 email="$(ynh_user_get_info --username=$admin --key=mail)"
 
 #=================================================
-# STORE SETTINGS FROM MANIFEST
+# STORE KEYS TO APP SETTINGS
 #=================================================
-ynh_script_progression --message="Storing installation settings..."
+ynh_script_progression --message="Storing secrets to app settings..."
 
 ynh_app_setting_set --app=$app --key=api_secret --value=$api_secret
 ynh_app_setting_set --app=$app --key=app_key --value=$app_key
 ynh_app_setting_set --app=$app --key=phantomjs_key --value=$phantomjs_key
-ynh_app_setting_set --app=$app --key=email_firstname --value="$email_firstname"
-ynh_app_setting_set --app=$app --key=email_lastname --value="$email_lastname"
-ynh_app_setting_set --app=$app --key=email --value=$email
 
 #=================================================
 # DOWNLOAD, CHECK AND UNPACK SOURCE
diff --git a/scripts/upgrade b/scripts/upgrade
index 91c535f..146c8e0 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -45,6 +45,20 @@ ynh_add_config --template="cron" --destination="/etc/cron.d/$app"
 chown root: "/etc/cron.d/$app"
 chmod 644 "/etc/cron.d/$app"
 
+#=================================================
+# ENSURE BACKWARD COMPATIBILITY
+#=================================================
+ynh_script_progression --message="Ensuring backward compatibility..." --weight=1
+
+# Delete deprecated `firstname`/`lastname` settings. See upstream https://github.com/YunoHost/yunohost/pull/1516
+ynh_app_setting_delete --app=$app --key=email_firstname
+ynh_app_setting_delete --app=$app --key=email_lastname
+ynh_app_setting_delete --app=$app --key=email # also delete unnecessary duplicate of state storage
+
+# Retrieve `$admin` user settings
+email_fullname="$(ynh_user_get_info --username=$admin --key=fullname)"
+email="$(ynh_user_get_info --username=$admin --key=mail)"
+
 #=================================================
 # UPDATE A CONFIG FILE
 #=================================================