diff --git a/config-raw.json b/config-raw.json
index 6c183d656..5691e7004 100644
--- a/config-raw.json
+++ b/config-raw.json
@@ -36,7 +36,7 @@
                 {
                     "key": "publicurl",
                     "default_value": "",
-                    "comment": "The public facing URL where your users can reach Vikunja. Used in emails and for the communication between api and frontend."
+                    "comment": "The public facing URL where your users can reach Vikunja. Used in emails and for the communication between api and frontend. The url must be a valid http or https url."
                 },
                 {
                     "key": "rootpath",