diff --git a/index.html b/index.html
index cdf477d..f25a0b1 100644
--- a/index.html
+++ b/index.html
@@ -119,7 +119,16 @@
         /**
          * (De)selects signatures based on the selection stored in a cookie.
          */
-        const loadSelectedSignaturesFromCookie = () => setSelectedSignatures(Cookies.get("selectedSignatures").split(","));
+        const loadSelectedSignaturesFromCookie = () => {
+            const cookie = Cookies.get("selectedSignatures");
+            let signatures;
+            if (cookie === undefined)
+                signatures = [];
+            else
+                signatures = cookie.split(",");
+
+            setSelectedSignatures(signatures);
+        };
 
         /**
          * Saves the currently-selected signatures to a cookie.