diff --git a/scripts/upgrade b/scripts/upgrade
index 04045f8..a616b8e 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -135,6 +135,8 @@ function list_installed_apps_not_compatible_with_future_version()
     comm -23 <(comm -23 $installed_apps $core_apps_in_current_version) $nextcloud_destination_appcatalog
 }
 
+current_version=$(grep OC_VersionString "$install_dir/version.php" | cut -d\' -f2)
+current_major_version=${current_version%%.*}
 
 last_version=$(ynh_read_manifest --manifest_key="resources.sources.main.url" | grep -o '[0-9][0-9]\.[0-9]\.[0-9][0-9]')
 last_major_version=${last_version%%.*}