diff --git a/riot.im/nightly/config.json b/riot.im/nightly/config.json
index 5b19550..e517b60 100644
--- a/riot.im/nightly/config.json
+++ b/riot.im/nightly/config.json
@@ -25,7 +25,8 @@
         "feature_invite_only_padlocks": "enable",
         "feature_event_indexing": "labs",
         "feature_bridge_state": "labs",
-        "feature_presence_in_room_list": "labs"
+        "feature_presence_in_room_list": "labs",
+        "feature_custom_themes": "labs"
     },
     "welcomeUserId": "@riot-bot:matrix.org",
     "piwik": {