diff --git a/dunstrc b/dunstrc
index 097e25d..e271511 100644
--- a/dunstrc
+++ b/dunstrc
@@ -36,6 +36,8 @@
     idle_threshold = 120
 
 [urgency_low]
+    # IMPORTANT: colors have to be defined in quotation marks.
+    # Otherwise the '#' and following  would be interpreted as a comment.
     background = "#aaaaff"
     foreground = "#000000"
     timeout = 10