diff --git a/target/scripts/startup/variables-stack.sh b/target/scripts/startup/variables-stack.sh
index fc38a39d..0b351a9e 100644
--- a/target/scripts/startup/variables-stack.sh
+++ b/target/scripts/startup/variables-stack.sh
@@ -83,6 +83,7 @@ function __environment_variables_general_setup() {
   VARS[ENABLE_FETCHMAIL]="${ENABLE_FETCHMAIL:=0}"
   VARS[ENABLE_GETMAIL]="${ENABLE_GETMAIL:=0}"
   VARS[ENABLE_MANAGESIEVE]="${ENABLE_MANAGESIEVE:=0}"
+  VARS[ENABLE_OAUTH2]="${ENABLE_OAUTH2:=0}"
   VARS[ENABLE_OPENDKIM]="${ENABLE_OPENDKIM:=1}"
   VARS[ENABLE_OPENDMARC]="${ENABLE_OPENDMARC:=1}"
   VARS[ENABLE_POLICYD_SPF]="${ENABLE_POLICYD_SPF:=1}"