diff --git a/.env.sample b/.env.sample
index 492c000..41dda22 100644
--- a/.env.sample
+++ b/.env.sample
@@ -42,6 +42,7 @@ COMPOSE_FILE="compose.yml"
 # CMD_CSP_REPORTURI=undefined
 # CMD_DEFAULT_PERMISSION=editable
 # CMD_EMAIL=true
+# CMD_REQUIRE_FREEURL_AUTHENTICATION=false
 # CMD_SESSION_LIFE=1209600000
 # Only present in config.json (no equivalent env var):
 # DOCUMENT_MAX_LENGTH=100000
diff --git a/compose.yml b/compose.yml
index b371675..20f41e7 100644
--- a/compose.yml
+++ b/compose.yml
@@ -25,6 +25,7 @@ services:
       - CMD_CSP_REPORTURI
       - CMD_DEFAULT_PERMISSION
       - CMD_EMAIL
+      - CMD_REQUIRE_FREEURL_AUTHENTICATION
       - CMD_SESSION_LIFE
       - DOCUMENT_MAX_LENGTH
     depends_on: