diff --git a/roles/custom/matrix-element-call/defaults/main.yml b/roles/custom/matrix-element-call/defaults/main.yml
index 972941d91..de507b704 100644
--- a/roles/custom/matrix-element-call/defaults/main.yml
+++ b/roles/custom/matrix-element-call/defaults/main.yml
@@ -9,6 +9,7 @@ matrix_element_call_backend_path: "{{ matrix_element_call_base_path }}/backend"
 
 # Docker network configuration
 matrix_element_call_container_network: "matrix_element_call_network"
+matrix_element_call_container_labels_traefik_additional_response_headers: {}
 
 # Docker images
 matrix_element_call_image: "ghcr.io/element-hq/element-call:latest"